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Full text of "73 Magazine (July 1997)"

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Including Ham Radio Fun! 



JULY 1997 

ISSUE #442 

USA $3.95 

CANADA $4.95 



International Edition 






Finally - A Professional- 
Quality Receiver to Monitor 
Weather Broadcasts! 



Our new RWX is a very sensitive and 
selective Hamtronics* grade receiver 
to monitor critical NOAA weather broadcasts. 

Excellent 0.1 5uV sen- 
sitivity provides good recep- 
tion even at distances of 70 

miles or more with suitable 
antenna. No comparison with 

ordinary consumer radios! 

Automatic mode provides storm watch P alerting you by 
un muting receiver and providing an output to trip remote 
equipment when an alert lone is broadcast. 

Essential for airports, police and fire departments. 
CAP. broadcast stations, stale and local emergency man- 
agers. amateur repeaters - anyone needing a professional 
quality receiver. Because of its reasonable price, rt is also 
handy for bikers, hikers, boaters, hunters, farmers — or 
anyone who needs up-to-date weather info and emer- 
gency warnings, even from distant stations. 

Small enough for emergency or portaWe use, it can 
even be powered from a small 9- 12V battery when 
needed Crystal controlled for accuracy; all 7 channels 
provided (162.40 to 182,65), 

You can buy just the receiver pch modute in kit form or 
buy the kit with an attractive meial cabinet, AC power 
adapter, and built-in speaker. It is also available factory 
wired and tested, 

* RWX Rcvr kit PCS onfy 379 

» RWX Rcvr kit with cabinet, speaker. & AC adapter „„,.,.. $99 

• RWX Rcvr wi red/tes ted in cabinet with speake r & adapter S 1 39 



WWV RECEIVER 



Get time and fre- 
quency checks 
without buying 
multjband hf rcvr. Hear solar 
activity reports affecting radio 
propagation. Very sensitive 
and selective crystal con- 
trolled superhet, dedicated lo listening to WvW on 10,000 
MHz Performance rivals the most expensfve receivers. 

• RWWV Rcvr kit, FCB only $59 

• RWWV Rcvr kit with cabt, spkr, & 12Vdc adapter ...S&9 

• RWWV Rcvr w/t in cabt with spkr & adapter .$129 






WEATHER FAX RECEIVER 



Join the fun. Get 
striking images di- 
rectly from the 

weather satellites I 
A very sensitive 
wideband fm receiv- 
er optimized for 
reception of NOAA APT and Russian Meteor weather 
fax images on the 137 MHz band. 

The R139 is lower cost and easier to maintain than 
synthesized units. And rt is designed from the ground up 
for optimum sate! file receptbn; not just an off-the-shelf 
scanner with a shorted* out IF filter! 

Covers all five satellite channels. Scanner circuit and 
recorder control allow you to automatically search for and 
tape signals as satellites pass overhead, even while away 
from home. 

* f\ K J3 ntBvVlTtfr OH It J3 W09C hri + l + bld hri 1-ta I i-l !■-! tri-t fcrft-aa t ■Tt- a *aB<t-«4t-hriiB-t M + l-4 tiH *- W I VV 

• R139 Receiver Kit with case and AC power adapter— S189 

• H 1 39 Receiver w/t in case wi!h AC power adapter. «^*r39 

• internal PC Demodulator Board and imaging Software 

• TumsSe Antenna _.__. 

• Weatrw Sabtte Handtoofc 



■ r«>ranwwr« 



i i iiiminu pi*""f» " 



$119 
120 




SUBAUDIBLE TONE 
ENCODER/DECODER 



Access all your favorite closed repeat- 
ers with TD-5 CTCSS Encoder/Decoder 



Encodes all standard sub- 
audible tones with crystal ac- 
curacy and convenient DIP 
switch selection Compre- 
hensive manual also shows 
how you can set up a front 
panel switch to select be- 
tween tones for several re- 
peaters. Receiver decoder 
can be used to mute receive audio and is optimized for in- 
stallation in repeaters to provide closed access. High 
pass filter gets rid of annoying buzz in receiver 

•TD-5 CTCSS Encoder/Decoder Kit only $39 

•TD-5 CTCSS Encoder/Decoder WiredrtestecL* ...$59 




HIGH QUALITY VHF & UHF FM 
XMTR AND RCVR MODULES 



FM EXCITERS; 2W output, continuous duty, 

• TA51: for 61^21^220 
MH2 ., kit S99, w/t $169. 

- TA451: for 420-475 MHz. 
.kit $99, w/t $169. 

• TA901: for 902*929 MHz, 
{O.BWout) , wft$169. 




VHF & UHF POWER AMPLIFIERS. 

Output levels from 10W to 100W Starting at $99, 




FM RECEIVERS: 

• R100 VHF FM RECEIVERS 

Very sensitive - 0. 1 5uV. Superb 
selectivity - both crystal and 
ceramic IF fitters, >100 dS 
down at ± 12kHz. best available 
anywhere, flutter-proof squelch. 
For 46^54. 72-76, 140-175. or 216-225 MHz .,.„,„„.. 

- R144/R220 RCVRS. Like R10Q\ for 2M or 220 MHz, 
with helical resonator In front end kit $159, w/t $21 9 

• R4S1 FM RCVR, for 420-475 MHz. Similar to R 100 
above kit $129, w/t $189 

• R901 FM RCVR, 9Q2-928MHz $169, w/t $219 



TRANSMITTING AND 
RECEIVING CONVERTERS M 



Go on a ham satellite adventure! Add an- 
other band for the next contest Thrill in the 
excitement of building your own gear, and 
save a bundle. 



Get more features for your dollar with our 

REP-200 REPEATER 



A microprocessor-controlted repeater with 
full autopatch and many versatile dtmf con- 
trol features at less than you might 
pay for a bare-bones repeater 
or controller alone! 




* ggpwP Mw 



* kit stiff only $10B5 

* factory assembled sffli orj/y $1 295 

S&-54, 143-174, 213-233, 420*478 MHz. (902*928 MHz slightly higher.} 
FCC typo accepted for oommsrcjaJ service in, 15O A 450 MHz bartda 




v^ 



Digital Voice Recorder Option. Allows message 
up to 20 sec to be remotely recorded off (he air. Play 
back at user request by DTMF command, or as a periodi- 
cal voice id, or both Great for making club announce- 
ments! „..„„* .„„„„, onty S100 

REP-200C Economy Repeater. Real-voice ID, no 
dtmf or autopatch. Kit only $795, w&t S1195 

REP-200N Repeater. Without controller so you can 
use your own „ Kit only $695, w&t S995 



You'll KICK Yourself 

If You Build a Repeater 

Without Checking Out Our Catalog First! 



Hamtronics has the world's 
4? most complete line of mod- 
MftV'7 tiles for making repeaters, tn 
JEW addition to exciters, pa's, and 
receivers, we offer the fol- 
lowing controllers. 

COR -3. Inexpensive, flexible COR module with timers, 
courtesy beep, audio mrxer. only 549/kit $79 w/t 

CWID. Traditional diode matrix ID'er kit only $59 

CWTD-2. Epron>comrolled IDer ..only $M/kil S79 wft 

DVR-1. Record your own voice up to 20 sec For voice 
id or playing club announcements SSftflcit $99 w/t 

COR -4, Complete COR and CWID all on one board. ID 
in eprom. Low power CMOS only $99/ktt $149 w/t 

CQR-6. COR with real-voice id. Low power CMOS, 
non-volatile memory kit only $99, w/t only $149 

COR-5. pP controller with autopatch, reverse ap, phone 
remote control, lots of DTMF control functions, all on one 
board, as used in REP-200 Repeater $379 w/t 

AP-3, Repeater autopatch. reverse autopatch. phone 
line remote control. Use with TD-2. kit $S9 

Four-digit DTMF decoder/controller, Five latching 
ff functions, toll call restactor ■■■■■,.„„„ kit $79 

TD-4. DTMF controller as above except one on-ofT func- 
tion and no toll call restricted. Can also use for selective 
calling, mute speaker until someone pages you, ,. kit $49 




No need to spend 
thousands on new 
transceivers for 
each band! 



Convert vhf and uhf signals toffrom 10M. 
Even if you don't have a 10M rig, you can pick up very 
good used xmtrs & rcvrs for next to nothing. 
Receiving converters {shown above) available for 
various segments of GM, 2M. Z20 h and 432 MHz. 
Kits from $49. wired/tested units only $99, 

• Xmltting converters (at 
left) lor 2M. 432 MHz 

• Kits onry SflS vhf or 
S99 uhf. 

• Power amplifiers up to 
50W output 






• Buy at low, factory-direct net prices and save! 

• For complete info, call or write for free catalog. 

• Order by mail, fax f or phone is-iz am, 1.5 pm eastern hmej. 

■ Mill, $5 S&H charge for Tint pound plus add'l weight & rn*urar«*. 

• Use VISA, Mastercard, Discover, check, or UPS COO. 



View Catalog on quf Web Site? 

www.hamtronics.com 
e mail: jv@hamtr0nic5.com 



LOW NOISE RECEIVER PREAMPS 



LNGH } G*A S FET PREAMPS 

STILL ONLY $59! 

» Make your friends sick with 

envy I Work stations they don't 

even know are there. 

• Install one at the antenna and 
overcome coax losses 

• Available for 28-30, 46-56, 137-15Z 152-172,210-230. 
400*470, end BOO-96Q MHz bands 

LNW-( ) ECONOMY PREAMPS 
ONLY $29 hit $44 wired/tested 
f • Miniature MOSFET Pie amp 

* Solder terminals allow easy 
connection inside radios. 
Available for 55-35, 35-55, 55-90, 90-120. 1 20-1 50. 
150-200, 200-270, and 400-500 MHz bands. 



■"^ISBi Tort 



amironics, mc 

66-D Moul Rd; Hilton NY 1446B-9535 

Phone 716-392-9430 (fax 9420) 



Synthesized 

FM Stereo 

Transmitter 




Microprocessor controlled for easy freq 
programming using DIP switches , no drift , your signal is rock 
solid all the time - jusl like the commercial stations, Audio quality 
is excellent, connect to the line output of any CD player, tape 
decto or mike mtoer and you're on-the-air. Foreign buyers will 
appreciate the high power output capability of the FM-25; many 
Caribbean folks use a single FM-25 to cover the whole island! 
New t improved, clean and hum-free runs on either 12 VDC or 
120 VAC. Kit comes complete with case set, whip anlenna, 120 
VAC power adapter - easy one evening assembly. 

FM-2S, Synthesized f M Stereo Transmitter Kil $129,95 



_-_ 



Tunable FM 

Stereo 
Transmitter 



A Jower cost alternative to our high performance transmitters. 
Offers great value, tunable over the 88-108 MHz FM broadcast 
band, plenty of power and our manual goes into great detail out- 

lining aspects of antennas, transmitting range and the FCC rules 
and regulations. Connects to any cassette deck, CD player or 
mixer and you're on-ihe-air, you'll be amazed at the exceptional 
audio quality! Runs on internal 9V battery or external power from 
S to IS VDC, or optional 120 VAC adapter. Add our matching 
case and whip antenna set tor a nice finished look, 

FM-1QA, Tunable FM Slereo Transmitter Kit $34,95 

CFM, Matching Case and Antenna Set. , SI 4.95 



RF Power 

Booster 

Amplifier 




Add some serious muscle to your signal, boost power up to 1 

watt over a frequency range ol too KHz to over 1000 MHz! 
Use as a lab amp for signal generators, plus many foreign users 
employ the LPA-1 to boost the power of their FM Stereo trans- 
mitters, providing radio service through an entire town. Power 
required: 12 to 15 volts IDC at 250mA, gain of 3&dB at 10 MHz R 
10 dB at 1QQ0 MHz, For a neat, professionally finished look, add 
the optional matching case set. 

LPA-1, Power Booster Amplifier Kit $39.95 

CLPA, Matching Case Set tor LPA-1 Kit $1 4.95 

LPA-1 WT, Fully Wired LPA-1 with Case $99.95 



wf^ 



Micro FM 
Wireless Mike 



World's smallest FM transmitter. Size of a sugar cube! Uses 
SMT (Surface Monti Technology) devices and mini electret con- 
denser microphone, even the battery is included. We give you 
two complete sets of SMT parts to allow for any errors or ' 
mishaps-build il carelulty and you've got extra SMT parts to 
build another? Audio quality and pick-up is unbelievable, trans- 
mission range up lo 300 feet, tunable to anywhere m standard 
FM band 88 Io108 MHz. TJffto % 3/BTi x 3/4"h. 

FM-S Micro FM Wireless Make Kit $19,95 



Crystal 

Controlled 

Wireless 

Mike 




Super stable, drift Iree, not affected by temperature, metal or 
your body! Frequency is set by a crystal in the 2 meter Ham 
band of 146.535 MHz, easily picked up on any scanner radio or 
2 meter ng. Changing the crystal to put frequency anywhere in 
the 140 to 160 MHz range-crystals cost only five or six dollars. 
Sensitive eleclrel condenser mike picks up whispers anywhere 
in a room and transmit up to 1/4 mile. Powered by 3 volt Lithium 
or pair ol watch batteries which are included. Uses the latest in 
SMT surface mount parts and we even include a few extras in 
case you sneeze and loose a pari! 

FM-6, Crystal Controlled FM Wireless Mike Kit, . . $39.95 

FM^WT Fully Wired FH-G > .. „„. $69.95 



Call for our Free Catalog ! 




Super Pro FM Stereo 
Radio Transmitter 




A truJy professional 
frequency synthe- 
sized FM Stereo 
transmitter station in 
one easy to use, 
handsome cabinet, 
Most radio stations 
require a whote 
equipment rack to 
hold all the features 
we've packed into the FM-100, Set frequency easily with the 
Up/Down freq buttons and the big LEO digital display.. Plus 
there's input low pass filtering that gives great sound no matter 
what the source (no more squeals or swishing sounds Irom cheap 
CD piayer inputs!) Peak limiters for maximum H punch r in your 
audio - without over modulation, LED bargraph meters for easy 
setting of audio levels and a built-in mixer with mike and line level 
inputs. Churches, drive-ins, schools and colleges find the FM-100 
to be the answer to their transmitting needs, you will too. No one 
otters all these features at this price! Kit includes sharp looking 
metal cabinet, whip antenna and 120 vol I AC adapter. Also runs 
on 12 volts DC. 

We also offer a high power export version of the FM-100 that's 
fully assembled with one watt of RF power, for miles of program 
coverage. The export version can only be shipped outside the 
USA, or within the US if accompanied by a signed statement that 
the unit will be exported. 

FM-100, Professional FM Stereo Transmitter Kit $299.95 

RI-100WT, Fully Wired High Power FM-100 * . $429.95 



Speech 

Descrambler 

Scrambler 




Decode all that gibberish! This is the 
popular descrambier / scrambler that youVe read about in all the 
Scanner and Etectronic magazines. The technology used is 
known as speech inversion which is compatible with most cord- 
Jess phones and many police department systems, hook it up to 
scanner speaker terminals and you're in business. Easily config- 
ured for any use: mike r line level and speaker output/inputs are 
provided. Also communicate in total privacy over telephone or 
radio, full duplex operation - scramble and unscramble at the 
same time. Easy to build, all complex circuitry contained in new 
custom ASIC chip for clear, clean audio Runs on 9 to 15V0C, 
RCA phono type jacks. Our matching case set adds a super nice 
professional look to your kit. 

SS-70A, Speech Descrambler/Scrambler Kit $39.95 

CSS 1 Custom Matching Case and Knob Set $14.95 

SS-70AWT, Fully Wired SE-70A with Case $79.95 

AC1M, 12 Volt DC Walt Plug Adapter $9.95 




Tone-Grabber 

Touch Tone 

Decoder / 

Reader 



I Dialed phone numbers, 
j repeater codes, control 
jcodes, anywhere touch- 
tones are used, your TG-1 will decode and store any number it 
hears. A simple hook-up to any radio speaker or phone line is all 
that is required, and since the TG-1 uses a central office quality 
decoder and microprocessor, it will decode digits at virtually any 
speed! A 256 digit non volatile memory stores numbers lor 100 
years - even with the power turned off, and an 8 digit LED display 
allows you to scroll through anywhere in memory. To make il easy 
lo pick out numbers and codes, a dash is inserted between any 
group or set ol numbers thai were decoded more than 2 seconds 
apart, The TG-1 runs from any 7 to 15 volt DC power source and 
is both voltage regulated and crystal controlled lor the ultimate in 
stability. For standalone use add our matching case set for a 
clean, professionally finished project. We have a TG-1 connected 
up here at the Ramsey factory on tne FM radio, It's fun to see the 
phone numbers that are dialed on the morning radio show! 
Although the TG- 1 requires less than an evening to assemble 
(and is fun to build, too!), we offer the TG-1 fully wired and tested 
in matching case for a special price, 

TG-1 , Tone Grabber Kil $99.95 

CTG. Wa1chino + Case Set for TG-1 Kit $14.95 

TG-1WT, Fully wired Tone Grabber with Case . , , $149,95 

AC12-5, 12 Veil DC Wall Plug Adapler $9,95 

CIRCLE 34 ON READER SERVICE CARD 



Mini-Peeper 
Micro Video 
Camera 



Super small, high quality 
fully assembled B & W 
CCD TV camera the size 
of an ice cube! Provides excellent pictures in low fight (2 lux), or 
use our IFM Infra-Red light source to invisibly illuminate an 
entire room on a pitch black night! Imagine the possibilities... 
build it into a smoke detector, wall clock, lamp, book, radio. 
Exact same camera that's in big buck detective catalogues and 
stores. Kit includes: fully assembled CCD camera module, con- 
nectors, interface PC board kit with proper voltage regulation 
and filtering, hook-up details, even a mini microphone for sensi- 
tive sound f Two models available: Wide Angle Lens 3.6mnVf2, 
adjustable locus lens, 92 degree view: Pinhole Lens 5.5mm/f4,5 n 
60 degree view. The Pinhole Lens is physically much flatter and 
provides even greater depth of focus. The camera itsell is )T 
square. The wide Angle Lens is about 1 " long. Pinhole Lens 
about M2\ Interlace PC board is V k 2" and uses RCA jacks for 
easy hook-up to VCRs, TVs or cable runs. Power required is 9 
to 14 VDC @ 150 mA. Resolution: 380 a 350 lines. Instruction 
manual contains ideas on mounting and disguising the Mini- 
Peeper along with info on adding one of our TV Transmitter kits 
(such as the MTV-7 unit below) Tor wireless transmission! 

MP'l, Wide Angle Lens CCD TV Camera Outfit S1 69,95 

MP-1Ph\ Pin-Hole Lens CCD TV Camera Outfit $1 89.95 




MicroS tat ion 
Synthesized 

UHFTV 
Transmitter 



Now you can be in the same league as James Bond. This 
transmitter is so small that it can fit into a pack of cigarettes - 
even including a CCD TV camera and battery! Model airplane 
enthusiasts put the MTV-7 A into airplanes for a dynamite view 
from the cockpit, and the MTV-7A is the transmitter of choice for 
balloon launches. Transmitter features synthesized, crystal con- 
trolled operation for drift-tree transmission of both audio and 
video on your choice ol frequencies: Standard UHFTV Channel 
52 {which should only be used outside of the USA to avoid vio- 
lating FCC rules), and 439.25 MHz or 91 1 .25 MHz which are in 
Ihe amateur ham bands. The 439,25 MHz unit has the nifty 
advantage of being able to be received on a regufar "cable- 
ready' TV set tuned to Cable channel 6B, or use our ATV-74 
converter and receive it on regular TV channel 3. The 91 1.25 
MHz unit is suited for applications where reception on a regular 
TV is not desired, an ATV-79 must be used for operation. The 
MTV-7 As output power is atmost 100 mW, so transmitting range 
is pretty much 'line-of-sighT which can mean many miles! The 
MTV-7 A accepts standard black and white or color video and 
has its own, on-board, sensitive electret micorphone. The MTV- 
7 A 3s available in kit form or fully wired and tested. Since the 
latest in SMT (Surface Mount Technology) is used to provide for 
Ine smallest possible size, the kit version is recommended lor 
experienced builders only. Runs on 12 VDC @ 150 mA and 
includes a regulated power source lor a CCD camera. 

MTV-7A, UHF TV Channel 52 Transmitter Kil $1 59.95 

HTV^AWT, Fully Wired Channel 52 Transmitter 5249.95 

HTV-7A4, 439.25 MHz TV Transmitter Kit ♦ , . . $1 59.95 

HTV-7A4WT, Fully Wired 439.25 MHz Transmitter $249.95 

HTV-7A9, 911.25 MHz TV Transmitter Kit * .,„ $179.95 

MTV-7AWT, Fully Wired 911-25 MHz Transmitter $269.95 

ATY-74, 439.25 MHz Converter Kit $159.95 

ATV-74WT, Fully Wired 439.25 MHz Converter $249.95 

ATV-79 f 91 1 .25 MHz Converter Kil , $179.95 

ATV-79WT, Fully Wired 91 1 .25 MHz Convene* ..._... $269.95 



RAMSEY ELECTRONICS, INC. 

793 Canning Parkway 
Victor, NY 14564 

Order Toll-free: 1-800-446-2295 

Sorry, no tech info or order status at this number 

Technical Info, Order Status 
Call Factory direct: (716) 924-4560 




Masfarfard 



-ft 



■Uh 



DIJG»V£R 



ORDERING WFO: Satisfaction Guaranteed. Examine toe 10 days, if nol 
pleased, return in original form for refund. Add $4.95 lor shipping, han- 
dling and insurance. Orders under $20, add S3 00 NY residents add 7% 
sales lax. Sorry, no CODs. Foreign orders, add 20% (or surface mail or 
use credit card and specify shipping method. 



& 



ASTRON 



9 Autry 

Irvine. CA 92718 
CORPORATION (714) 458-7277 • FAX (714) 458-0826 



www.astroncorp.com 



SWITCHING POWER SUPPLIES 




CONT, 


!CS 


WT.(LBS) 


SS^10 


7 


10 


3.2 


SS-12 


10 


12 


3.4 


SS-18 


15 


18 


3.6 


SS-25 


20 


25 


4.2 


SS-30 


25 


30 


5.0 




SS-25M With volt & amp meters 
SS-30M With volt & amp meters 



SLSE 




RS-L SERIES 




ASTRON POWER SUPPLIES 

HEAVY DUTY • HIGH QUALITY • RUGGED • RELIABLE 



SPECIAL FEATURES 

• SOLID STATE ELECTRONICALLY REGULATED 

• FOLD-BACK CURRENT LIMITING Protects Power Supply 
from excessive current & continuous shorted output 

• CROWBAR OVER VOLTAGE PROTECTION on all Models 
except RS 3A, RS-4A, AS-5A. RS-41.. RS 5L 

• MAINTAIN REGULATION & LOW RIPPLE at low line input 
Voltage 

• HEAVY DUTY HEAT SINK • CHASSIS MOUNT FUSE 

• THREE CONDUCTOR POWER CORD except for RS-3A 

• ONE YEAR WARRANTY • MADE IN U.S.A. 



PERFORMANCE SPECIFICATIONS 

* INPUT VOLTAGE: 105-125 VAC 

* OUTPUT VOLTAGE: 13.8 VDC ± 0,05 volts 
(Internally Adjustable: 11-15 VDC) 

• RIPPLE Less than Smv peak to peak (full load & 
low fine) 

• All units available in 220 VAG input voltage 
(except for SL-11A) 



* LOW PROFILE POWER SUPPLY 

Colors Continuous 



MODEL 

SL-11A 
3L-11R 
SL-11S 
SL-11R-RA 



Gray Slack Duty lAmps) 



■ 
* 



7 
7 
7 

7 



ICS* 

[Ampsl 

11 
11 
11 
11 



Size UNI 
H*W*B 

m * m * m 

2%*7 *9^ 
2% * Tk *W* 
4 3 /4*7 *9^ 



*tJ 



Wt 



12 
12 
12 
13 



* POWER SUPPLIES WITH BUILT IN CIGARETTE LIGHTER RECEPTACLE 

Continuous ICS* 

MODEL Duty (Amps) (Amps) 

RS-4L 3 4 3ft*6'A*7V4 

RS-5L 4 5 3ft*6V fl *7% 



Size UK] 



Shipping 
WL (lbs!) 



RM SERIES 




19" RACK MOUNT POWER SUPPLIES 

Continuous 
MODEL Duty {Amps) 



MODEL RM-35M 



RM-12A 

RM-35A 

RM-bOA 

RM-60A 

Separate Volt and Amp Meters 

RM-12M 

RM-35M 

RM-5QM 

RM-60M 



9 
25 
37 
50 

9 

25 
37 
50 



IDS* 
lAmps) 
12 
35 
50 
55 

12 
35 
50 
55 



Size UN) 
H x W x 

5*Ax19xBV4 

5 V* x 19 x 12 1 /s 

5%x19x12V2 

7 x 19 x 12V? 

StixWxBV* 
5%x19x12Va 

5V^x19x12 1 /2 

7xl9x12Y? 



Shipping 



Wt 



16 
3& 
50 
60 

16 
38 
50 
60 



RS-A SERIES 




MODEL RS-7A 



MODEL 

RS-3A 

RS-4A 

RS-5A 

RS-7A 

RS-1QA 

RS-12A 

RS-12B 

RS-20A 

RS-35A 

RS-50A 
RS-70A 



Colors 
Gray Black 



* 



* 

* 
* 



Cantinuaus 
Duty (Ampi| 

2.5 

3 

4 

5 

7.5 

9 

9 

16 

25 

37 
57 



IDS 4 

(Amps) 

3 

4 

5 

7 

10 

12 

12 

20 

35 

50 
70 



Size |IN| 
H X W X D 

3 X 4V4 X 5^ 
3 3 /< X 6V 2 X 9 

3Vz x m x 7V< 
m x 6 1 £ X 9 

4X 7V?x 10V-i 
4V2 X 6 x 9 

4 X 7V? x 10 1 /* 

5 X 9 X 1QV2 
5 x 11 X 11 

6 X 13 3 /i X 11 

6 x 13^ x 12^ 



Shipping 
Wt. (lbs.) 

4 

5 

7 

9 

11 

13 

13 

18 

27 

46 

48 



RS-M SERIES 




MODEL RS-35M 



MODEL 

Switchable volt and Amp meter 
RS-12M 

Separate volt and Amp meters 

RS-20M 

RS-35M 

RS-50W 

RS-70M 



Cifilinuius 
Oity (Amps) 



16 

25 
37 
57 



ICS' 

lAttpiJ 

12 

20 

35 

50 
70 



Size [IN) 
M x W X 

4ft X 6 X 9 

5 X 9 X Wk 

5X 11 X 11 

6xt3 a AX 11 
6 x 13V< x 12% 



Shippihg 
Wt. |lbt.) 

13 

18 

27 

46 

48 



VS-M AND VRM-M SERIES 



• Separate Volt and Amp Meters * Output Voltage adjustable from 2-15 volts • Current limit adjustable from 1 ,5 amps 




MODEL VS-35M 



RS-S SERIES 




MODEL RS-12S 



w run umu 






Continuous 






ICS* 


Size (IN) 


Snipping 


MODEL 






Duty (Amps) 






(Amps) 


H x W x D 


Wt. (lbs | 






@13.0VDC @10VDC @5VDC 




@mv 


r 




VS^12M 




9 


5 




2 




12 


4 1 £ X 8 X 9 


13 


VS-20M 




16 


9 




4 




20 


5 x 9 x Wk 


20 


VS-35M 




25 


15 




7 




35 


5x 11 x11 


29 


VS-50M 




37 


22 




10 




50 


6x 13¥<x 11 


46 


VS-70M 




67 


34 




16 




70 


6x13^x12^ 


48 


Variable rack mount power suppl 


es 














VRM-35M 




25 


15 




7 




36 


5tt x 19 x 12tt 


36 


VRM^SOM 




37 


22 




10 




50 


5ti x 19 x 12ft 


50 


Built in speaker 


I 


Colors 


CflfltiMM* 


IDS' 




SIM (IN] 


Shipping 


MODEL 


Gray 


Black 


Dity (Anps) 


Anps 




H X W X D 


Wt. (lbs.) 


RS-7S 


# 


• 




5 




7 




4 x7ft x10^ 


10 


RS-103 


• 


» 




7.5 




10 




4 x7V* x10ft 


12 


RS-12S 


■ 


i 




9 




12 




4 1 6 X 8 x 9 


13 


RS-20S 


* 


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16 




20 




5X9 X 10Vz 


18 


SL-11S 


• 


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11 




2 3 A x Tk x m 


12 



* ICS— Intermittent Communication Service (50% Duly Cycle 5m in. on 5 mi n. off) 



CIRCLE 16 ON READER SERVICE CARD 



THE TEAM 

El Supremo & Founder 
Wayne Green W2NSD/1 

Associate Publisher 
fe I, Marion 

Associate Technical Editor 

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Nitty Gritty Stuff 

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Prisciila Gauvtn • 

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Mike Bryce WBSVGE 
Joseph E. Carr K4IPV 
Michael GeierKBlUM 
Jim Gray W1 XU/7 
Jack Heifer KB7NO 
Chuck Houghton WB6IGP 
Dr. Marc Leavey WA3AJR 
Andy MacAllister W5ACM 
Dave Miller NZ9E 
Joe Moell K0OV 
Steve Nowak KE8YN/5 
Carole Per ry WB2MGP 

Advertising Sales 
Frances Hyvarinen 
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603-924-0058 
800-274-7373 
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Circulation 
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Business Office 

Editorial - Advertising - Circulation 

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73 Amateur Radio Today Magazine 

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Including Ham Radio Fun! 

Amateur 
Radio Today 

TABLE OF CONTENTS 



JULY 1997 

ISSUE #442 



FEATURES 

10 ATV is Here to Stay!-W5ACM 

Getting started with amateur television. 

14 How to See What You Hear— KC50DM 
WARNING! This is easy! 

1 9 C-Sand Law Noise Amplifier— WD5BQN 

Use discarded satellite revolver parts to soup up your ATV system. 

21 Video Titlers for ATV-N5JXO 

If you're serious about ATV r a video titter is the way to go. 

27 Antennas for Amateur Television, Part 1 — K0NM 

An overview of the most useful, 

32 Home-brew Yagis For Amateur Television— N5EM 
Easy to build, easy to use-^and not just for beginners! 

35 Rocket Video - KC5AWJ 

Video beyond the speed of sound. 

41 Tiny Power— KC50DM 

A big little switcher tor ATV (or other) uses 

45 Finding His Voice— Sanders, KB6MTV 

Two young women found an urgent need for CW skills. 

47 Bicycles Across Switzerland— N0BF 

ORPing through beautiful Switzerland by bicycle is a blast! 

81 Lets Keep CW Alive! -WF6P 

Its distinctive, its useful and— most of alt— if $ fun! 

83 Help for College-Bound Hams-NBPGt 

Apply for an amateur radio scholarship. 



DEPARTMENTS 



WB6IGP 


57 


Above & Beyond 




73 


Ad Index 


KB1UM 


75 


Ask Kaboom 


WB8ELK 


50 


ATV 




88 


Barter 'n' Buy 


K41PV 


76 


Carr's Corner 


KB7NO 


71 


The Digital Port 


WB2MGP 


62 


Hams With Class 


W5ACM 


56 


Hamsats 


NZ9E 


59 


Ham to Ham 


K0OV 


52 


Homing In 




6 


Letters 


W2NSD/1 


4 


Never Say Die 




G3 


New Products 


KE8YMG 


80 


On the Go 


W1XU 


87 


Propagation 


WBSVGE 


54 


QRP 




8 


QRX 


34,54,61,62, 


Radio Bookshop 


79,82,86,88 




WA3AJR 


74 


RTTY Loop 




72 


Special Events 



HAM RADIO FUN SECTION 



REVIEWS 



24 

38 



Dr. Nicad Battery Conditioner/Rapid Charger— WU0L 

Ramsey Electronics Model No. DN-1, 
Full Rock and Roll-AA0XI/VK5FN 

The AT- 11 Automatic Antenna Tuner from LOG Electronics. 



K20AW 64 



NV7IG6 6fl 



Communications Simplified, 
Part 19 

Multiplexing and digital data. 
Vintage Review: 
Yaesu FT-727R Dual- Bander 

Save money on an all-purpose 
HT. 



On the cover: Al Wright of Huntsville, Alabama, prepares HALO ATV rocket for maiden voyage to 
30,000 feet. Photo by Bill Brown WB8ELK, See "Rocket Video" (page 35) and "ATV" (page 50) for 
high attitude adventure. Need some cash for that new rig? Send us your possible cover shot photos, 
gladly returned if not purchased. 



Feedback: Any circuit works better with feedback, so please take the time to report on 
how much you like, hate, or don't care one way or the ottier about the articles and 
columns in this issue. G = great!, O = okay, and U = ugh. The G T s and O's will be 
continued. Enough U's and it's Silent Keysville. Hey f this is your communications 
medium, so don't just sit there scratching your, .er,.. head, FYI: Feedback "number" is 
usually the page number on which the article or column starts. 



73 Amateur Radio Today (ISSN 1052-2522) is published monthly by 73 Magazine, 70 N202, Peterborough NH 
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Contract: By being so nosey as to read this fine print, you have just entered into a binding agreement with 73 
Amateur Radio Today. You are hereby obligated to do something nice for a ham friend— buy him a subscription 
to 73. What? All of your ham friends are already subscribers? Donate a subscription to your local school library! 



Number f on your Feedback csrd 



Neuer srv die 



Wayne Green W2NSD/1 



What More 
Can 1 Say 
About Hamfests? 

A note from Wall Bastow 
N4KVF suggested I comment on 
the disintegration of our major 
liLiinK-sis. Okay. 

When around l Ni r * of the local 
hams don't bother to go to a 
hamfest or convention it should 
be taken as a sign by the orga- 
nizing committee that maybe the 
eveni isn't perceived as worth 
the time and price. Not enough 
fun, Bo-o-oring. 

As Tve pointed out before, 
I went to my first ham test in 
1938 and though the world has 
changed beyond belief, hamfests 
havenX As with the code, ama- 
teur radio seems firmly mired in 
its past— anchored there by the 
ARRL and its CW- fixated board. 
Take a look at a I c J 3 7 issue of 
QST and tell me what differ- 
ences you find in 1997, sixty 
years Later, Small cosmetic 
changes have been made, and 
that's about it. About 70% of the 
magazine is still advertising and 
club news. 

If hamfests are going to sur- 
vive they need to be re-invented. 
With attendance dropping fast, 
it's getting harder to attract ex- 
hibitors. The main things a 
hamfest has to offer are the com- 
mercial ham exhibits, the Ilea 
market, and speakers. How 
many hamfests have you both- 
ered to attend in the last couple 
of years? If any one of them had 
an exciting speaker, please drop 
me a QSL card with his name. In 
my experience there's a good 
reason whv the talks at hamfests 
draw so few listeners — they're 
dull. I've sampled many of 
them, just to see for myself. 

I've already written about my 
ideas for making hamfests into 
1990s entertainment, but I've 
seen no sign that anything has 
changed. 

With around 60% of today's 

A 73 Amateur Radio Today • July 



hams feeling disenfranchised by 
the League becau.se they are 
Novices or Techs, they're not 
big on joining ham caravans 
driving to the big hamfests. 
Their ham friends are all in their 
local repeater area, not spread 
around the country. And they are 
not enough into ham satellites 
and other ham special interests 
to want to spend the time and 
money to get together with simi- 
larly-interested hams from out- 
side their area. 

I've never seen any hint in the 
mam club newsletters I get, nor 
any word from a reader, suggest- 
ing that any hamfest committees 
have done any opinion surveys 
to find out what hams like and 
don't like about hamfests. So 111 
do one right now. 

If you've been to a hamfest in 
the last couple of years, what 
part of it was the most fun for 
you? What might the hamfest 
committee do that would make it 
more fun? Have you passed up 
going to any hamfests. and if so 
why? Can hamfests be salvaged 
or has their day passed? 

A few years ago CQ Magazine 
announced they were launch- 
ing a series of commercially 
run hamfests. Far's I know the se- 
ries ended with the first gigantic 
flop. 

One of the problems. I suspect 
has to do with money. Hamfests 
can be very profitable for the 
organizers, with one group re- 
putedly skimming hundreds of 

■ * 'tap 

thousands of tax-free dollars. 
This has tended to continually 
increase both the attendance 
price and the cost of booths for 
exhibitors, while keeping pro- 
motional and other expenses to a 
minimum. With so much money 
floating around and so little ac- 
countability, there's bound to 
be mischief. And since most 
hamfests are chaired by a ham 
with little experience in running 
big events or in dealing with 
large amounts of cash, it's no 

1907 







wonder we hams have, in the 

long run, been shortchanged. 

I'd like to see hamfests used 
more as promotional events to 
get kids interested in the 
hobby, with major promotions 
to bring the kids in and enter- 
lain/educate them. How about 
a ham in a balloon with an 
HT talking with kids on the 
ground, complete with a ham 
video camera showing the guy 
in the balloon talking? 

How about a slow-scan TV 
demo with someone in Africa or 
Europe on schedule, letting the 
kids talk to the chap they're 
looking at? Now you think up 
some stunts which will get the 
kids excited. 

Folks, it's grow or go. Your 
choke, but please don't look 
around for any leaders to follow. 

We haven't any, 

NASA Confirms 

Cold Fusion Excess Heat! 

Using a nickel-potassium car- 
bonate (light water!) cell NASA 
scientists con finned and recon- 
firmed the cold fusion excess 
heat phenomenon. Using differ- 
ent current levels and one pulsed 
current test their power gains 
ranged from 1 .06 to L68< The 

tests were run by the NASA 
Lewis Research Center Croup in 
Cleveland, Ohio using a cell 
borrowed from Hydrocatalysis 
Power Corporation. 

The cell had previously been 
producing "Fifty watts of steady 
excess heal for a continuous 
period exceeding hundreds of 
days.** 

The report concludes, "Con- 
sidering the large magnitude of 
benefit if this effect is found to 
be a genuine new energy source. 
a more thorough investigation 
of evolved heat in the nickel- 
hydrogen system in both electro- 
lytic and gaseous loading cells 
remains warranted." 

The report covers the history 



of the Pons-Fleischmann an- 
nouncement and the quickly- 
following negative reports from 
Harwell, CalTech and MIT— 
which, interestingly enough, 
easily found publication in sci- 
entific journals, while positive 
reports were denied publication. 

The report points out that 
modern cells of various types 
"have power multiplication fac- 
tors over 10. and have achieved 
powers as high as -4kW/cm\ If 
true, such data clearly exclude 
by orders of magnitude an ordi- 
nary chemistry explanation and 
force one to consider various 
I attice- assisted nuclear chan- 
nels." 

NASA's obvious interest is as 
a "power source to replace radio 
isotope thermal generators for 
planetary spacecraft." 

Considering, from what we 
know 1 now, that the cell used 0.5 
mm nickel wire for the cathode* 
we can understand the delays in 
loading hvdroaen into the nickel 
lattice, and the relatively lov* 
power gains achieved. Patterson 
and his CETI group have been 
reporting gains in the K000 and 
up range using powdered and 
thin-films of nickel. 

You can gel your very own 
copy of this NASA report by 
asking for N96-22559, My Con- 
gressman, Charlie Bass, got one 
for me. 

Will word of this NASA re- 
port ever reach the Department 
of Energy? 

Nut 

Nut 
Nut 
Nut Case 



I plead guilty to being a nut. 
I'm a radio nut, a car nut, a cam- 
era nut, a health nut, a UFO nut, 
a ski nut. a scuba nut, a gourmet 
nut, and so on. Oh yes, a com- 
puter nut too. And a classical 
music nut and cold fusion nut. 
Fm so nutty I practically rattle 
when I jog. 

Now, with my health nut 
beanie in place, propeller spin- 
ning, driven almost to levitalion 
speed by the force of my ema- 
nating brain waves, let's talk 
about the biocieemficr. Yes. it's 
a great little gadget, and ridicu- 
lously simple to build and use. 
But it does tend to cater to the 
need for people's immediate 
gratification. 

The more I read about health, 
the more the pieces all fit 
together — and the picture is a 
mess. Let me explain. 



If you want to have a healthy 
body you need to provide it with 

the raw materials your body 
used as it developed over the 
course of a million vchj> or so. 
The main reason we're sick and 
dying 20-30 years before we 
need to is oar not providing our 
bodies wilh the building materi- 
als they were developed to use. 

Like what? Heck, we've got 
one of l he best food supplies in 
the world, right? 

Umm, not quite. Yes, I've writ- 
ten about some of this before, but 
you need a refresher 

Your body needs air. water. 
sunlight, the foods it was de- 
signed to use. exercise, and a 
relative freedom from stress. 
It also needs a freedom from 
poisons. 

Take water, for instance. Just 
look at the stuff you've been 
drinking! It's got added fluo- 
rides, chlorine, dioxin. lead, 
copper, and stuff like thai. Are 
you drinking distilled water yet? 
Are you drinking at least eight 
glasses of distilled water every 
day? Thaf s what the body uses 
to help flush out the poisons 
which would otherwise accumu- 
late. There are four excellent 
books on water in my guide to 
books you're erazv if vou don't 
read. 

Sunlight. Sure, too much can 
be damaging, but for 99% of us 
(or more) it's loo lit lie. We keep 
those "harmful" UV rays out of 
our eyes with glasses, windows, 
mill so on. [f you'll read a eOUpte 
of btx)ks on light by Ott and 
Liebcrnian you'll be oul there 
with your glasses off getting L'Vs 
into your eyeballs on your morn- 
ing walks. Our eyes and skin need 
sunlight. In moderation. 

The worst, is our food supply. 
[lev, don't believe me about this, 
put me down as a nut. But at 
least do me the courtesv of do- 
ing your homework. Dr. Joel 
Wallach and his "Dead Doctors 
Don't Lie" tape may have some 
exaggerations, bui he's right 
about the vitamins and minerals 
bein^ long gone from our super* 
market foods. You either take 
supplements or you get sick and 
die. Usually painfully. Read his 
Let's Plav Doctor book — also 

- 

his Rare Earths* which Til have 
to add to my reading guide. Do 
your homework and then tell me 
I'm a nut. 

You must have read about all 
the cmd they're putting in our 
meat supply. Antibiotics, hor- 
mones, and so on. That just 
makes ihose Whoppers and Big 



Macs all the more deadly. And 
the movie theater popcorn 
popped in artery -clogging goo. 

Pois Like alcohol, nico- 

tine, aspartame, mercury, fluo- 
rides, caffeine, immunization 
shots. 

Two of m> favorite TV pro- 
grams are "The Simpsons*' and 
"Roseannc." Both feature big fm 
constipated-gut beer-drinking 
fathers* 1 enjoy the programs for 
the writing, though Roseau lie's 
show has gone downhill sub- 
stantially since losing Dave 
Raethcr as an associate pro- 
ducer. Both fathers spend most 
of their time drinking beer and 
watching ball games on TV, 
What a terrible way to waste 
one's life. Instead of learning 
and contributing to the world, 
they sit staring dumbly and 
poisoning their bodies. Great 
role models. 

Our ancestors spent a lot of 
time oul in the sun, got lots of 
exercise, and ate mostly raw 
fruits and vegetables grown in 
mineral-rich soil. No poison 
sprays. 

By the way, if you'll read Se- 
crets of the Soil, you learn that 
insects only attack sick crops. If 
you give the crops the minerals 
they need instead of chemical 
fertilizers the bugs won't bother 
them. 

Far's I know they don't teach 
any of this stuff in school. Not 
even college. So how can a per- 
son find out about how bad our 
water and food supplies are and 
what to do to live a healthy life? 

How many really healthy 
people do you know? My mother 
fed me pretty well when I was a 
kid. so 1 had such outstanding 
teeth that dentists would call in 
their assist anis to look at them 
when I had my checkups. It wasn't 
until after I went away to college 
and then joined the Navy that I 
had to have my first filling. It 
wasn't until my sophomore year 
in high school that 1 even lasted 
soda pop or a Coke. White bread 
and sugar? Cold cereals? No way! 
I still love all hot cereals, and 
without any sweetening. 

Once you start doing your 
homework I'll bet you'll get ex- 
cited over thinking and start 
making a similar nuisance out of 
yourself trying to get others to 
turn off the TV and start reading. 
The mind is like a muscle; the 
more you use it the stronger it 
sets. 

So let's stan with stuff that 
has an immediate application in 
making you healthier. If you 



give your body a break you're 
not going to need a bioelectri ti- 
er to get rid of viruses, microbes. 
parasites, yeasts, and fungi in 
your blood because your im- 
mune system won't permit them 
to set up shop in the first place. 
Our bodies come with a fantastic 
error detection and repair sys- 
tem. Given an even break vour 
maintenance system will keep 
you stroke, cancer, and Alz- 
heimer's free for life. You can go 
visii your old friends in their 
nursing homes, and then visit 
their children in the same homes 
a generation later. 

Now, isn't it about time to 
start repairing the damage 
you've done to vour body? 
You've got a truly amazing re- 
pair system built in — one thai 
can keep you alive despite all 
the poisons and poor nutrition 
you've insulted it with. Jusl give 
it a real chance to do its work. 

If my lecturing is annoying, 
shrug it off. But what I wish 
you'd do is make a list of your 
chronic illnesses and then seri* 
ously change your pattern ofliv- 
ing and keep track of the gradual 
elimination of fat. arthritis, and 
so on. And lei me know that I've 
helped. 1 can live with the cat 
calls and ridicule from the non- 
thinkers if I'm able to reach a 
few readers and help them have 
happier lives. 

Stress? Yep, that's a big factor 
too. Indeed, every illness has a 
p s yc hoi og i C a I co m pone n l , so 
maybe it's lime to start solving 
your stress problems. 

End of lecture, For now. 

Quid Pro Quo 

That's Latin for getting some- 
thing for something, Like what 
does the public get from us in re- 
turn for our allocation of billions 
of dollars in frequencies? 

A 13-page special invitation to 
join the AARA as an alternative to 
me ARRL almost got me lo think- 
ing. Now, if ihe American Ama- 
teur Radio Association were a le- 
gitimate (in my eyes) group, at 
this critical time in our history I'd 
say that it would he folly to get in- 
volved in a civil war. 

So, am I saying, "In union 
there is strength," join the 
ARRL? The strength of a union 
is only there when the union 
members have some say in the 
running of their union, and from 
everything I've seen, the aver- 
age ARRL member hasn't even a 
nano- voice in the ARRL. The 
ARRL Board will listen to you 



up until they get your member- 
ship check. When you send in 
your membership you are paying 
for some hoped-for future ser- 
vice (like the survival of the 
hobby). When you refuse to pay 
up until you see some significant 
signs thai you are going to get 
the service you want, thai puts 
pressure on ihe tight-knit old- 
boy group running the League 
to actually do something. 
They'll do a lot to get your 
money, but little once they have 
it. That's just plain old human 
nalure at work. 

The AARA, a.k.a. Glen Baxter 
KLV1AN, looks to me like a new 
pyramid scheme wilh Section 
Managers getting a 10'* piece of 
the action for evcrv new recruit 
and Slate Directors getting 5 c k. 
Membership seems to be $35 a 
year- Then there's the Ameri- 
can Amateur Radio Council 
(AARC), where membership 
costs $250 a year. That's a divi- 
sion of the AARA, Then there's 
the Amateur Radio Management 
Consultants (ARMCh the Foun- 
dation for the Advancement of 
Amateur Radio (FAAR). the Do- 
mestic Amateur Radio Emer- 
gency organization [DARE), the 
American Amateur Radio Digest 
(AARD). a monthly newsletter. 
the International Amateur Radio 
Network (IARN), the Amateur 
Radio Peace Corps Foundation 
(ARPCFh the American Ama- 
teur Radio School (AARS). And 
so it goes. Ii looks to me as if 
(Hen has built a 'Totcmkin Vil- 
lage" one-man organization in 
order to take advantage of the 
present weakness of the ARRL. 

The League's stand on the 
code has made it seem irrelevant 
to about 60% of the licensed 
hams. Talk about a death- wish ! 

Worse, from what Gien Baxter 
is saying, he's blaming the ARRL 
for the influx of no-code hams and 
promises his AARA will push for 
"higher quality hams." He calls 
the ARRL "corrupt, petty, irrel- 
evant, and overly commercial," 
wilh a "Neanderthal Mental 
Midget Mentality," He seems to 
be concentrating entirely on his 
pyramid of Section Managers to 
si i lie it membership from already 
licensed hams rather than push- 
ing them to get kids involved 
10 build up our numbers. No 
mention of that. 

I've found Glen to be a ded- 
icated man — overwhelmingly 
dedicated to promoting GIen + 

We don't need a civil war in 

hamdom right now — what we 

Continued on page 26 

73 Amateur Radio Today • July 1997 5 



Letters 



Number 6 on your Feedback card 



Bill Ma vers, Canastota NY. 

» 

In the May issue of 75, you said 
you had never received a negative 

report on the Bioenergizer/' I 
sen! you such a report, and you 
ignored it. Shortly after it was first 

described in your magazine* I 
built one and began using it. J told 
you that within six months, I de- 
veloped irritable bowel syndrome 
and diabetes , and began experi- 
encing migraines. You did nol re- 
spond. You have a habit of taking 
the "medical establishment" lo 
I ask for failing to own up to lhe 
fact thai some of their products 
can be hazardous. Wayne, to fail 
to tell your readers that 1 have 
found this device lo be dangerous 
(diabetes is a deadly disease), you 
are being even more dishonest, by 
pretending to be a guardian of 
your readers' well-being, yet 
pushing a useless and dangerous 
product. Show us there is a dif- 
ference between Wayne Green 
and the crack -dealing creeps who 
lurk around our children's 
schoolyards. Print a retraction. 

By golly, you are right and I 
was wrong, I should have said 
that I hadn V received any cred- 
ible negative reports. Diabetes, 
eh? Normally thai fakes several 
years of misuse of one's body to 
develop. And migraines normally 
stem from the same cause as irri- 
table bowel svndrorne. You have 
not been doing your homework 
and I have. Both the Coca and 
Wallach books, which are recom- 
mended in my guide to books 
you* re crazy if you don't read, 
cover these two allergy problems -. 
These symptoms have nothing to 
do with any virus, microbe* para- 
site, fungus or yeast in the blood, 
By the way, Wallach covers the 
cause and a simple cure for dia- 
betes in his book. Vve already 
written about why crack dealers 
are making so much money. We 
can thank the government for that 
beaut. Based on the Albert 
Einstein College of Medicine dis- 
covery and patent, plus the re- 
ports from Bob Beck and quite a 
few readers, the bioeiectrifier 
makes good scientific sense tome 
t can see where, after extended 
use, one would want to replace 

6 73 Amateur Radio Today * July 



From the Ham Shack 

any lost beneficial microbes via 
acidophilus milk. I am anxious to 
hear about any positive or nega- 
tive effects, Is this going to turn 
out to be the medical industry's 
worst nightmare, or just another 
placebo exciter ? , , . Wayne . 

Michael Borer WL7CKB, 

Anchorage AK. Re the AC5HU 
comments on the ARRL "code 
survey," I am sure glad to find 
someone else thai was not taken 
in by the "Anti-Revisionism Ra- 
dio Louts" either. The ARRL 
sends out an opinion poll on 
whether or not to keep the ANTI- 
QUATED CW requirement for 
HF licensing and what do they 
do? They "Sing to the Choir" of 
the already converted. Now 1, for 
one, am definitely not in favor of 
the elimination of CW from our 
bands, but since all the ITL" re- 
quires is a "knowledge of code** 
to qualify for the HF bands, and 
since even the FCC, in their "No- 
tice to Physician," on the back of 
the Form 61 G, states that a 5 wpm 
proficiency is ail that is required 
for our physically challenged 
hams, why should the rest of us 
be forced to meet the overinfhited. 
arbitrary and capricious code 
speeds? 

While the ARRL continues to 
discriminate against the vast ma- 
jority of licensed amateurs, there 
is one group, the "Code 5" group, 
headed by Guy Matzinger 
KB7PNQ, 503 Dubois St., 
Cheney WA 99004-1 325, fighting 
to have the code requirement re- 
duced to a sane 5 wpm speed- All 
interested, licensed hams should 
contact Mr. Matzinger and sign 
the petition that he is circulating 
and even help financially, if at all 
possible, so that he can go before 
the FCC with a bis stack of ham 
signatures in favor of a change in 
licensing policy. 

Now. I know that there are 
those out there that will scream 
that we arc trying to lower the 
standards for receiving a ham li- 
cense, but nothing could be far- 
ther from lhe truth. Since this is a 
technical hobby, not a physical 
training hobby, I would propose 
a toughening of lhe technical 

1997 



aspects of the exam, not perhaps 
to the point of having to draw and 
build a circuit, but definitely hav- 
ing to learn about antennas, 
packet and all the various modes 
of communication. If we want lo 
push the technological envelope 
again, as we once did, it is defi- 
nitely time to quit wasting our 
precious time with a physical 
training exercise, and learning a 
mode of communication that \ ir- 
lually all other entities, both pri- 
vate and government, have 
discontinued using. 

Good grief, another trouble- 
maker! ...Wayne. 

Lionel C. Allen VK6LA, 

South Como WA* Here's a bit of 
midnight reading for you, Your 
April 73 mentioned dowsing, 
Here's an experience 1 had years 
ago. Dowsing with an odd twist 
1 was on Air Force leave and vis- 
ited a very respected and quite 
elderly neighbor right across the 
road from where my family lived. 
He had taught my brother, some 
12 years older than myself a loi 
about black and white photogra- 
phy, as he did with me years later, 
On this visit the general talk 
turned to dowsing. Not just the 
simple finding-water stories, but 
also health diagnosis by utilising 
various minerals held in his hand 
and short-length pendulums, I 
seem to remember being diag- 
nosed as having a shortage of 
some mineral or other. Quite 
frankly, I didn't believe ihe sto- 
ries he told, but on the other hand, 
this gent just did not tell lies. Ad- 
ditionally, he had all his experi- 
ments care fully written in a small 
notebook. 

Then we went outside to carry 
on some traditional water dows- 
ing. My elderly neighbor was ab- 
solutely certain he could teach rue 
ihe basic an of finding not only 
fresh water, hut trails of impure 
water created b\ seweuiic con- 
taincd in underground plumbing. 
If the neighbors thought it a bit 
weird as a 19-year-old and an S0- 
year-old wandered up and down 
the yard hand in hand, they dido* l 
comment. For my part, though, 
not i single twitch was generated 
from pieces of wire, various 
twigs, and so on. 

Some time later I was posted 
to a fairly remote location at an 



Air Force transmitter station in 
Northern Australia. With only six 
staff in all, and as it was an easy- 
going job. 1 took to walking some 
of the trails well marked by. and 
used by, Australian aboriginals. 
Purely by chance, I one day broke 
off a small branch of a tree and 
soon had a traditional dowser's 
forked branch held out in front of 
me. To my astonishment, the 
dowsing fork gave a very strong 
reaction in two separate locations 
not far from where the camp was 
set up. I traversed the area for a 
good hour, but only those two 
exact locations gave any response 
over a good half mile or so. I went 
back to our small mess and spread 
the word! 

Naturally, there were the usual 
nudge-nudge, wink-wink re- 
marks, but enough enthusiasm 
was aroused for others to try their 
skill 1 explained the general idea 
and got four of the other Tellers 
lined up at a good distance apart 
and headed them off down the 
track I had just walked. I declined 
to tell them where the actual 
dowsing reaction had occurred. 
Also. I asked them not to indicate 
to each other if and where they 
mi&ht receive anv dowsing re- 
sponse. Again, and you've 
guessed correctly, in the exact 
same locations fouroui of the five 
of us got reactions, The general 
dowsing enthusiasm lasted long 
enough to convince several of us 
there really was somelhing in this 
business after all 

However, the story isiu quite 
complete. As enthusiast number 
one 1 dowsed lhe whole damned 
area without any other really good 
responses' That is, until one day 
I began to realize that every rime 
I headed out around lhe camp and 
under every overhead feeder line 
from the transmitter station, I got 
a strong response. Obviously. 
from the overhead lines. For some 
reason. I was the only one of the 
six to ect these reactions. Now, 
the feeders from the reasonably 
large number of antenna systems 
covered a lot of territory. As oth- 
ers didn't get the same reaction, 
it was either provide liiiiliei proof 
or call the men with the little 
white coal. 

So, well and truly blindfolded, 
1 was guided around the general 
area and periodically under the 



open wire overhead feeders. Well, 
blindfolded or not, 1 was infal- 
lible! So how about that for a 
twist, Wayne? I hope one of your 
books doesn't have a method of 
making a million out of overhead 
feeder line dowsing because I 
never ever found any use for it, 
At least I was convened from a 
nonbeliever to a firm believer and 
had a fair bit of ftm in the process, 
Hey, I wonder if it stemmed 
from the group I played with as a 
youngster- — we were the greatest 
kite flying enthusiasts for miles 
around. With plenty of open space 
around in those days, a dozen or 
so of us would take off with kites 
up high and well out in front of 
us in the afternoon sea breeze. All 
power reticulation was overhead, 
but we would take off in line and 
walk slowly for I'd say about a 
miie. At each block the older kids 
would run out some extra string 
and then hurl the ball over the top 
of the power lines! I never once 
recall seeing a ball caught up 
in the power lines but 1 guess it 
happened- At the end of the walk 



we'd reel in the kites and walk 
back home. 

F ve never ever since seen kids 
repeat that sort of kite flying. 
Maybe I was lucky. Perhaps I was 
lucky to spend a lot of time liv- 
ing with my aunt and uncle on a 
wheat and sheep farm. Many 
times we would harness two or 
more large kites together and 
launch one of the farm dogs up 
for a ride up in a bag harness. We 
never ever had a complaint from 
the dogs and they apparently 
didn't mind too much either, as 
they would always join us from 
day to day. Not that I recall ever 
getting one up much higher than 
twenty feet or so. I'd reckon not 
too many kids did that either! 

Gosh, and 1 was going to tell 
you how Fve been trying to whip 
up a bit of enthusiasm in amateur 
radio. Never mind, I'll write 
again. Now you can go back to 
sleep! 

ZZZZZZZZ- Lionel, this is a ham 
magazine and you* re supposed 
to write about ham radio, not 
dowsing and kites. Got that? On 






dowsing, any nudge-nudgers 
should not read the Owen Lehto 
book, Vibrations, which is .,. of 
course ...in my reading guide .♦. 
Wayne. 

Jan Medley KB0WQT. 73 

has a well deserved reputation for 
"pot stirring'* and I usually regard 
that as a big plus, But sometimes 
a columnist goes right off the rails 
and needs a reality check. Such 
was the case with Joseph Can's 
column in your May issue. 'There 
is no excuse for offering MS-DOS 
software any longer " says Mr. 
Can. He's entitled to his opinion, 
but he should know better than to 
make such categorical, unsup- 
ported statements with complete 
disregard for the facts, As a long- 
time personal computer user of both 
Windows and DOS software, 1 
found the column insulting, mis- 
leading, and generally worthless — 
even if one ignores the question of 
what a column on software design 
might be doing in a ham radio 
magazine. Here arc some facts: 
1 . First and foremost* Windows 



95 (and its predecessors) is ... wait 
for it ... a DOS program. It is a 
GUI and a number of utilities for 
memory management and hard- 
ware management including 
multi-tasking, but if you look un- 
der the hood you will find that 
DOS is still there as the Disk 
Operating System, For whatever 
reasons, Microsoft may have 
fooled a lot of people by chang- 
ing file names and "kemelizing" 
DOS, but you have to look to NT 
in order to find a version of Win- 
dows that is actually an operat- 
ing system in its own right. This 
is a lost battle, I know, and the end 
result is that most users will think 
Windows is an OS, but the point 
is that anything that can be writ- 
ten for DOS can run "under" Win- 
dows, and any Windows program 
is ipso facto a DOS program as 
well. 

2, Not everyone can afford the 
hardware necessary to support a 
Windows 95 installation. Starting 
price is close to $2,000, while 
DOS machines are commonly 
Continued on page 55 




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73 Amateur Radio Today • July 1997 7 



c/ff ff . . . 



Number 8 on your Feedback card 



New "Ark" for WB6N0A 



After 20 years of faithful emergency communi- 
cations service- Ihe Gordon West WB6NOA black 
station wagon will retire and "NOAs ARC* a new 
Amateur Radio Communications vehicle, will take 
over Gordo indicates the new ARC unit will be used 
for classroom demonstrations as well as VHF/UHF/ 
microwave expeditions. 

This new unit will be added lo our water-grid 
arsenal, now allowing us the capabilities of attend- 
ing regional ham shows, and having all of our mi- 
crowave equipment onboard," he said, It wil) also 
serve as an emergency communications vehicle for 
our local American Red Cross chapter, plus emer- 
gency communications for the city of Costa Mesa/ 

West's new communications vehicle is built 
around a Chevrolet 22-fooi G30. a 1-ton extended 
van chassis with a 7.4 liter 454 CID EFI V8 gas 
engine. There will be a 4.5kW generator installed 
beneath the rear radio operating area to provide 
plenty of power for all the amateur radio equipment 
onboard. 

The upper portion of the vehicle, built by Home & 
Park Motorhomes in Ontario t Canada, is called 
"Roadtrek/The roof is Fiberglas™. but contains built- 
in copper screening tor good RF shielding between 
the antennas and the passenger compartment 

"All of the antennas will feature Eip-mount and 
gutter-mount technology from the leading antenna 
manufacturers like Diamond and Comet. We will 
also have a motorized antenna lay-down mount from 
Maldol," West continued. 

His idea of "no holes" was to specifically test the 
new generation of antenna mounts thai secure firmly 
to almost any ridge, lip, or metal edge, "We will even 
run a full-length, high-frequency whip off of the rear 
door tire mount, and again, we will go only with off- 
the-shelf antenna mounts available at all ham radio 
stores," he added. 

Built into the screen area separating the metal 



sides of the vehicle and the Fiberglas roof will be 
an automatic high -frequency antenna coupler with 
a long-wire attachment. "This could allow us to string 
up a long wire, using the screen as well as the chas- 
sis sides of the vehicle for a great ground plane 
system," he said, *We will also be able to put a strong 
signal on 75m, the coordination band for weak-sig- 
nal trapo and meteor scatter work." 

Long-boom yagi antennas will be earned on the 
inside of the vehicle. The booms would be sepa- 
rated so as not to exceed the length of the vehicle. 
The yagis would operate either fixed-direction or, 
for now T via the "Armstrong" rotor system. 

When ft comes to the ham radio equipment on the 
inside, West claims that each and every manufacturer 
of amateur radio equipment will be represented. 

"We will have 160m through 10,000MHz .„ and 
this will allow students to enjoy hands-on exposure 
to every brand sold through dealers or direct, and 
this way our mobile classroom will support every- 
one rn the industry equally." adds West. 

Plans also call for large magnetic signs, indicat- 
ing AMATEUR RADIO ON THE AIR r so that the 
vehicle may also travel as an amateur radio infor- 
mation center "We plan to make this unit very vis- 
ible during amateur radio operating events like Field 
Day and Simulated Emergency Tests, We will also 
carry amateur radio information packages, includ- 
ing amateur radio magazines, ARRL inlormaiion 
sheets, and ham publications, along with manufac- 
turer frequency charts and Welcome to Ham Radio 
guides/' West sums up, 

There will be three operating positions inside the 
vehicle: the front for high-frequency; midsection for 
VHF and UHR and the rear area thai will carry sat- 
ellite and data equipment. 

"I look forward to working many stations on the 
air from IMOA's ARC/ smiles West. Plans call for a 
West Coast "shakedown," and then looking Into 
other engagements throughout the rest of the coun- 
try, Gordon West's wife. Suzy West N6GLF, looks 
forward to driving while "Gordo" scurries around 
inside, keeping everything on the air "ARC Mobile." 




ARRL Calls on FCC to 
Privatize Handling of 
Malicious Interference 
Complaints 

Citing - a substantial need to improve and in- 
crease the quantity and quality'' and timeliness of 
enforcement in malicious interference complaints, 
the ARRL has called on the FCCto "create a stream- 
lined, privatized enforcement process" to handle and 
adjudicate the most serious Amateur Service rules 
violations. In a petition for rulemaking filed March 
28. the League asked that the FCC change its rules 
to permit members of the volunteer Amateur Auxil- 
iary to bring evidence of maJfCious interference vio- 
lations directly before the Chief Administrative Law 
Judge. The chief AU would be authorized to deter- 
mine if the complainants have a valid case, to issue 
show-cause orders, and to designate complaints for 
hearing. 

The League recommended lhal the FCC capi- 
talize on Ihe volunteer resources available through 
the Amateur Auxiliary to relieve the evidence*gath* 
ering burden in such cases. If the mles + changes 
are approved, the League said it would likely assist 
members of the Amateur Auxiliary in preparing and 
submitting complaints and in presenting cases at 
administrative hearings, The increased use of vol- 
unteer resources would seem to be entirety appro- 
priate in the Amateur Service, which involves 
avocational use of radio only/ the ARRL concluded. 

While noting that most hams obey the rules, the 
League said Amateur Radio needs the commission's 
help "in a very few, persistent serious enforcement 
cases" but has not been getting it in recent years 
because of the FCCs staff and budgetary limita- 
tions. 

Indeed, notwithstanding the best efforts of the 
Commission over the past several years, there has 
been no resolution of the four or five most serious 
cases brought to the Commission's attention/' the 
League said in its petition. Even in some of the cases 
the FCC did act upon, the League said the Com- 
mission did not go far enough to make the prob- 
lems go away permanently. The League cited a case 
tn New Orleans where fines against several ama* 
teurs were reduced but remain unpaid and uncol- 
lected. There is a widespread, and growing, 
perception that administrative forfeitures are not 
collectable." the ARRL said T pointing to the com- 
plex, time-consuming method of collecting fines that 
is required by federal Jaw. Trie ARRL noted that while 
the FCC suspended one ham's license in that city 
in 1996. it failed to look into malicious interference 
charges against at least two other hams in that area. 
The League said examples like these send a mes- 
sage that the FCC won't enforce Amateur Service 
rules in malicious interference cases. Informal me- 
diation attempts also have tailed. "Malicious inter- 
ference problems, if left unchecked, tend to spread 
and increase in intensity." the League said. The 
ARRL suggested that a series of "visible, success- 
ful enforcement actions" would deter rules violations 
and promote setf-regulation + 

The ARRL also suggested that some FCC poli- 
cies get in the way of timely, effective enforce*nent, 
Current Wireless Telecommunications Bureau policy 
requires the Commission to independently 



8 73 Amateur Radio Today • July 1997 



corroborate evidence gathered by Amateur Radio 
volunteers. The policy often acts as an absolute 
obstacle to any enforcement activity whatsoever" 
and it demoralizes volunteers, who view their ef- 
forts a& wasted, 

While noting that malicious interference cases 
often attract a Jot of attention within the amateur 
community, the League said ham radio can be "jus- 
tifiably proud" of its history of voluntary rule compli- 
ance, 'The overall level of compliant behavior 
among amateurs has not deteriorated over the 
years," the League emphasized, citing fewer than 
10 active malicious interference cases in the US at 
present. 

TNX Tuned Circuit monthly bulletin of the UAnse 
Creuse (Ml) ARC, May 1 997, from the ARRL letter. 



Lights! Camera! Action 



Some ham radio paraphernalia supplied by the 
ARRL will appear in the upcoming Warner Broth- 
ers™ film, Contact. The League loaned the movie 
makers vintage Q$T$ and other publications and 
maps for use In the production. Mike Gastaldo of 
WB's props department said the radio shack scenes 
"happen in the first 15 minutes of the film, You can 
tell people to go for the ham radio scenes and stay 
for the astrophysics." 

Gastaldo expressed thanks to the League for 
"helping us to portray Amateur Radio in as realistic 
and positive a way as possible. 11 The movie is sched- 
uled to open July 11.— ARRL. 

From the Tuned Circuit, monthly bulletin of the 
L'Anse Creuse ARC (Ml), April 1997. 



Phase 3-D Launch Delayed 
Until September, 1997 

Paris, France (AMSAT News Service)— In a for- 
mal announcement from Paris on March 24th, the 
European Space Agency (ESA) said that the sec- 
ond test flight of their new Ariane 5 booster has now 
been rescheduled from July to mid-September, 
1 997. It Is this flight, Ariane 502, on which Phase 3- 
D Is currently manifested. 

According to their latest announcement this ac- 
tion was being taken by ESA and CNES {the French 
Space Agency which manages the Ariane 5 pro- 
gram for ESA) in order to Improve (the booster's) 
robustness r increase the operational margins and 
allow for degraded operating modes." 

In a joint statement a day after the ESA an- 
nouncement, Phase 3-D Project Leader and 
AMSAT-DL President, Dr. Karl Meinzer DJ4ZC, 
along with AMSAT-NA president Bill Tynan W3XO, 
expressed continuing confidence that ESA and 
CNES will succeed in completing all the tasks nec- 
essary for a successful flight test of Ariane 502. 

"Naturally we were disappointed that our launch 
will not be as soon as we had hoped," said Meinzer. 
"However, I am pleased that ESA and CNES are 
taking care to improve the operational margins for 
the Ariane 5 booster. This action helps give us re- 
newed confidence in the overall probability for a 
successful launch of our satellite." 

Both Meinzer and Tynan emphasized, however 



that this launch delay, like the earlier ones, means 
that the total cost of the Phase 3-D Project will 
increase significantiy. Even before the latest ESA 
announcement AMSAT-DL and AM SAT-MA were 
projecting a combined budget shortfall of about two 
hundred thousand dollars (US) in the money needed 
to complete their respective tasks on the project. 

This shortfall can only increase now as a result 
of this latest schedule change," said Tynan. Both 
AMSAT leaders urged everyone to continue doing 
as much as they possibly can to ensure the needed 
funds will be in place for the completion and launch 
of Phase 3-D. 

From AMSAT news release, March 19, 1997. 



CQC Top Ten Signs You've 
Been a Ham Too Long 



10. You refer to the kids as "harmonics. n 

9, Every 1i me you make a mortgage payment you 
think about what sort of rig you could buy for the 
same money. 

8. Towers, yagls, and odd bits of wire in the air 
look "pretty." 

7. Your car license plate has your callsign on it. 

6. You use Q-signaJs in everyday speech. 

5. Your first consideration in looking for a new 
home is where the antennas will go. 

4. Your mobile rig is worth more than your car. 

3. You refer to your kids boom-box as a "rig." 

2. You have jockey shorts with your callsign em- 
broidered on them. 

And the number one sign You've Been a Ham 
Too Long: 

% Two words: u dit dil* [Ed Note: A CQC inside 
joke— it's the trademark signoffofQRPguru K5F0.] 

From Low Down, official journal of the Colorado 

QRP Club (cqc@aoi.com). 



Repeaters: How They All 
Came About 



Once upon a time, there lived a scattered group 
of persons who wanted desperately to talk with other 
persons who lived in the far away berry patches. 

After much deliberation, they selected one of their 
clansmen who just happened to live atop a big hill 
and who had a big mouth— and excellent hearing. 
The one in the valley yelled remarks to the top of 
the hill, where the top man then repeated what he 
heard so that all listeners, everywhere, would know 
what was being said from here and there. 

Now it happened that some individuals could not 
hear the voice from atop the hill in good fashion. 
Also, some of the traveling salesmen riding their 
donkeys in some distant valley remained unan- 
swered because their voices fell upon empty air 

There were some souls in some geographical 
spots that had been taught to whistle just right be- 
fore they yelled to the re-sayer. Unless he recog- 
nized a certain whistle, he refused to do any 
hollering for them. 

All in all, it was a happy experience for most folks. 
In fact it was suggested that the idea be put upon a 
stone tablet and preserved for posterity. It was done. 



Author unknown; the ARNS Bulletin, April 1997 ; 
got this from the SERA Repeater Journal, Decern- 
ber 1996. 



What To Do 
About the Code 



Amateurs are fascinated with coded transmis- 
sions, We bitch, moan and complain endlessly about 
the CW testing requirements forced on the Ama- 
teur community and then insist on using every CW 
u Ocode" known to man while working the local clear 
channel repeater. 

I guess, to prove that you are a "real 1 ' ham : you 
must use as much "Radio Speak" as possible, but it 
does take a little bit of practice to become really 
proficient. 

I just heard an GM on 2 meters going to QRX 
(he didn't say when). Often we will QSY to "you 
know, that other frequency" for private QSOs and, 
when we go home to the QTH after work the XV L 
will often force us to QRT at dinner time- 
How often have you been QRM h d recently? Not 
to mention the constant problems with GSB and the 
fight with QRN in the summer. I never know when I 
am going to be QRX'd and I am never really sure of 
my QRY on the net I never know the QTR (prob- 
ably because I have two watches) and no one ever 
agrees with my QTB. 

I hate guys (and gals) that QSK me and then are 
unabie to QSL because they have not been QRV 
when I CQ. 

The FCC encourages the use of phonetics as 
formulated by the ITU when encountering QRM or 
when signals are GRJ< The object of which is, of 
course to facilitate communications and avoid mis- 
takes. This can be real fun depending on who is on 
the other end of the QSO. Since most of us don't 
bother to learn the current version of the phonetic 
alphabet (at least not all of it) the simple A-B-C-D 
can become: 

Able, Baker. Charlie, Dog or... America, Bolivia, 
Canada, Denmark or... Alpha Bravo, Charlie. Delta... 
all of which, depending on your age, are, or at least 
were, acceptabie phonetics, 

Then there are those who must invent their own 
phonetics. When this occurs, N2VPN can become: 
NoahVTwo-Very-Peculiar-Nomads, 

By John Buzby N2VPN in Harmonics, South Jer- 
sey Repeater Association, April 1997, 



The Bones of the Organization 

1. The wishbones: those who wish somebody 
(else) would do something. 

2. The jawbones: those who talk about the prob- 
lem, but do little else. 

3. The knucklebones; those who knock every- 
thing—especially the backbones. 

4. The backbones: those who carry the load, but 
usually don't say much. 

What type of Bone are you? 

Think about it! 

TNX ARNS Butietin, April 1997; Coliector and 
Emitter November 1996; Counterpoise, November 
1994. eZ] 

73 Amateur Radio Today ■ July 1 997 9 



Number 10 on your Feedback card 



ATV is Here to Stay! 



Getting started with amateur television. 



Andrew C. MacAllister W5ACM 

14714 Knights Way Drive 

Houston TX 77083-5640 



Amateur television, or just ATV, 
can refer to fast-scan TV thai we 
see at home on the "tube," slow- 
scan TV that periodically produces a 
new still picture (depending on the for- 
mat), or something in between. The 
transmission of images as digital files, 
via terrestrial or satellite links, can also 
be considered amateur television. But 
the real fun comes back to the first defi- 
nition. Full-color, lull-motion, fast-scan 
TV is gaining popularity and acceptance 
in the amateur community, 

My first ATV experience dates to a pe- 
riod when HF transceivers had more 
tubes than transistors, VHF-FM was 
new to most hams, and to change fre- 
quency up there, you had to buy new 
crystals for the desired channel. Amateur 




Photo A* HATS ATV transmitter site repeater 
antennas. 

10 73 Amateur Radio Today • July 1997 



television enthusiasts operated on UHF 
frequencies, above most "normal" ham ac- 
tivity. They had equipment that most hams 
couldn't recognize, understand, or afford. 
The ATVers of that day were either elec- 
tronics design engineers, or worked in the 
TV broadcast business, or both. 

Home movies were made with wind- 
up or battery-powered 8mm movie cam- 
eras. Tape decks were for audio. Tripods 
were for film- type still cameras. Most 
TV signals were broadcast. Cable TV 
was rare, and satellite TV was little more 
than an expensive experiment. 

Today's home movies are made using 
camcorders with tripod connections- 
New styles of electronic still cameras 
are coming out every day. Video cassette 
recorders are everywhere. Many have 
cable TV. Those who don't probably 
have cable-ready TV sets or recorders. 
Satellite TV systems can be purchased at 
the local mall or discount store. Times 
have changed, and so has ATV. 

Getting started with ATV is much 
easier now. Many of the ingredients for a 
home television station may already be 
on hand. To make things easier, answers 
to frequently-asked questions can be 
quickly found on the Internet. In addi- 
tion, there are magazine articles, 
columns and books about ATV, along 
with equipment manufacturers produc- 
ing amateur television gear, ready for 
purchase, right off the shelf. 

Ultimate simplicity 

For those hams fortunate enough to 
have an active local ATV club running a 
well-located television repeater system, 
shifting a few wires in the shack may be 
all that's needed to receive ATV 

The local Houston, Texas, repeater 



(W5PZP) has a standard amplitude- 
mod ul ated television output on 
421.25MHz. This corresponds directly 
to cable channel 57, For those within a 
few miles of the repeater, signals can be 
received with a cable-readv TV set con- 
nected to an outside UHF antenna. The 
repeater transmitter is often commanded 
for continuous transmission of test pat- 
terns or information screens to facilitate 
testing of home and mobile receive 
equipment (Photos A, B, C). 

For those who don't have a local TV 
repealer with output on 421,25MHz, 
there are alternatives. A nearby ham with 
an ATV transmitter can provide some 
video to Lest a simple receive setup. 
Most direct AM-ATV activity on 70cm 
occurs on 426, 434 or 439,25MHz. 
These frequencies correspond roughly to 
cable channels 58 r 59 and 60. Home sta- 
tion transmitters are not generally used 
on 421 .25MHz, due to the close proxim- 
ity of the band edge at 420MHz, Sup- 
pression of the lower sideband com- 
ponents requires special filters , usually 
found only in commercial transmitters 
and better ham repeater systems. 

The Houston Amateur Television So- 
ciety (HATS) Web pages include a sec- 
tion describing "How to get on ATV 
CHEAP". Check out the Universal Re- 
source Locator (URL) [http://www 
.stevens.com/hats/]. The suggested mini- 
mum system includes a simple 440MHz 
beam (the club sells an inexpensive kit), 
a mast-mounted preamp and a TV tuned 
to cable channel 57, With adequate 
height (outside and just above the roof), 
enthusiasts have been able to see the 
repeater out to 25 miles. 

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Photo B. Monitors and tontrolters at the 
HATS ATV repeater transmitter site, 

have been able to use their 70cm satellite 
antennas to monitor ATV activity when the 
satellites are below the horizon. In addi- 
tion to various ATV-orienled activities 
through the repealer, the Houston AMSAT 
net is earned on the local system. 

The next level 

Competition lor spectrum within the 
amateur allocutions continues to acceler- 
ate. ATV in Texas has not been immune 
to pressures from closed repealer and 
link systems in ihc 7()cm band. For the 
most pan. cooperation has won out over 
confrontation between the voice and 
video camps. While the audio-only link 
proponents have expanded into the tradi- 
tional ATV 70cm spectrum, the video 
supporters have looked to higher fre- 
quencies for clear channels. The groups 
have worked together, to keep interfer- 
ence at a minimum for the 421.25MHz 
TV repeater channel, and to avoid the 
435-438MHz satellite band 

The 23cm or 1.2GHz band is 60MHz 
wide. This bandwidth can support a lot 
of modes without con diet. The Houston 
group maintains an in-band FM televi- 
sion repeater on 23cm with an output on 
1 285MHz. This is the same signal that is 

12 73 Amateur Radio Today * July 1997 



transmitted on 421.25MHz AM, the 
preferred entry -level receive frequency. 

While 1,2GHz television operation 
may at first seem to be a formidable 
task, only for radio and TV gurus, it is 
not. Many hams have put systems on 
line to receive 1 .2GHz FM TV for less 
than S50. The methods are surprisingly 
simple, requiring no home-brew gear or 
design work. 

The recent migration of satellite tele- 
vision viewers to K-band (1 2- 1 40 Hz) 
digital and subscriber systems has pro- 
vided a surplus of older FM satellite re- 
ceivers with inputs compatible with 
1.2GHz ham television. 

There are several types of satellite- 
TV receivers circulating on the ham 
swapmeet circuit. The one to look for is 
designed for the C-band (4GHz) or Ku- 
band (12GHz) LNB (low-noise block 
downconverter). The LNB is placed at 
the focal point of the satellite-TV dish, It 
amplifies the satellite signal and down- 
converts the 5G0MHz-wide passband to 
950- 1450MHz, This signal is typically 
fed through 75-ohm coax (RG-59 type) 
to the receiver. The receiver is tunable 
through the 950 to 1450MHz range, thus 
covering the 1.2GHz ham band, but is 
rather insensitive since it expects a 
rather strong signal from the LNB. Re- 
ceivers of this type can usually be pur- 
chased for $30 to $70. The simpler, mure 
inexpensive, receivers with analog inn- 
ing and few extras arc easier to use for 
ham TV. 

Getting one of these receivers on the 
air is simple; Add a preamp and a 
1.2GHz beam antenna. The FM-TV sig- 
nals broadcast by the TV satellites arc 
typically wider than those used by ama- 
teur TV systems. Simply increasing 
the receiver's output video level will 
provide a quick fix. 

Transmitting 

While getting something on line thai 
can receive signals from a nearby ATV 
enthusiast or repealer can be easy, tran^ 
milting TV is more challenging. Even if 
all the gear is purchased, rather than 
home-built, attention to detail is impera- 
tive. At 70cm and 23cm* RF connectors. 
cable and antenna quality is key. Most 
ATV stations incorporate kb N" connec- 
tors, low-loss coax like Belden 9913 or 
better and high-gain antennas. Al 
1.2GHz, even a 100- loot run of 9913 



will lose up to 75% of the signal. Many 
stations with runs this long have gone to 
7/8-inch hardline, or remote power am- 
plifiers. Check the specifications, and 
buy ihe besi you can afford, 

ATV is a very unforgiving mode. If 
the path between two stations will sup- 
port narrowband FM UHF communica- 
tions at 40 to 50dB over S 9. TV will 
probably work. Trees and buildings can 
cause multipath problems, or ghosts, 
or may even prevent communication 
completely. 

There are several sources of ATV 
transmitter gear. A few of the more well- 
known companies include HP Technol- 
ogy, (847) 639-4336: PC Electronics. 
(818) 447-4565; Pauldon Associates, 
(716) 692-5451: and Wyman Research, 
r3 17) 525-6452. Most also carry receiv- 
ers, receive converters, preamps and an- 
tennas. Clubs like HATS have taken the 
initiative to design and build kits for an- 
tennas, preamps. filters and transmitters. 
This provides the club with funds for re- 
peater repair and upgrades, while at the 
same time allowing members to get on 
the air for less money and to learn more 
about TV technology. 




Photo C Tower supplies and amplifiers at 
the HATS ATV repeater transmitter site. 



Why ATV? 

Interactive television is an intense 
mode. Unlike typical voice communica- 
tions, where you can monitor a conversa- 
tion from the other side of the room while 
soldering a circuit togeiher. ATV requires 
your attention. To participate in a "conver- 
sation/" you must watch and listen. When 
transmitting, you may be running tapes, 
displaying devices in front of a camera, or 
trying to get a computer screen to look 
right over the air, 

It's also not something that you do while 
mobile. In fact it can be quite dangerous, 
A lew hams in Houston have managed to 
rig cameras and transmitters that can run 
without intervention while driving, hut 
they rely on the signal reports from moni- 
toring stations to make any adjustments. 
It's illegal for drivers in many states to 
have a TV set in viewing range. Most ATV 
is done while at home, or al least from a 
stationary position. 

After you've shown off the kids, dogs, 
cats, all the stuff in the shack and all the 
old home movies, what's left? The answer 
is only as good as your imagination. The 
South Texas Balloon Launch Team has 
been using ATV for many years to transmit 
live television back from altitudes over 
100,000 feet (Photo D). The HATS group 
televises club meetings and license-up- 
grade classes around Houston. Unlike 
commercial broadcast television, ATV is 
two-way. Stations can "talk back" to the 
class or club meeting with either two- 
meter FM or their own live television, 

HATS members also enjoy volunteer 
activity during community activities that 
use TV coverage for event coordination. 
Each year the members go to the streets to 
transmit live TV from the Houston Meth- 
odist Marathon and the March of Dimes 
Walk America (Photo E). As the club 
grows, so does the potential of the group to 
cover more events and pawidc useful pub- 
lic service. While event officials see live 
action along the course route, so do hams 
around town. Some experimenters use 
ATV on radio-controlled airplanes and 
cars, while others have even launched 
ATV in very large model rockets. 

Due to the unforgiving nature of ATV. 
most hams pursuing this mode are con- 
stantly upgrading their equipment. More 
power, bigger antennas, and better leedline 
are primary targets. Station enhancements 
can include more or newer cameras, belter 
lighting, video/audio switch boxes and 




Photo D. HATS member Rick Pense WD5BQN prepares for 1.2GHz ATV reception of a South 
Texas balloon launch. 



VGA to NTSC converters to get com- 
puter images on the air While ATV sta- 
tions used to keep old ham license plates 
around for video identification (ID) 
screens, new inexpensive video tillers 
have taken over. Experiments with re- 
mote-controlled cameras and transmit- 
ters are also fun. In addition to activity in 
the 70cm and 23cm bands, efforts on 
higher frequencies past 10GH/. are not 
uncommon. ATV is a good place to learn 
advanced RF techniques. You can "see" 
the results. 

Finding out more about ATV is easy. A 
look at the Internet can get things started. 
In addition to the HATS Web page at 
(http://www.sievens.com/hats/]. 
Amateur Television Quarter l\ Mae a- 
zine (ATVQ) maintains pages via the 
same provider Check out ATVQ's page 
at f http://wwwVslevens.com/alvq/ 1. Both 
HATS and ATVQ provide many links to 
clubs, manufacturers and distributors 
around the world. While at the ATVQ 
site, note that a magazine subscription i 
form is part of the home page. ATVQ 
comes out four limes a year and offers a 
fine magazine dedicated to the pursuit of 
amateur television. Henry Ruh KB9FG, 
the publisher, also offers an array of 
books and other publications. A very 
popular two-volume publication from 
ATVQ provides history, tutorials and 



technical information about amateur 
telex ision. The first part is called ATV 
Secrets for Aspiring ATVers (S9.98). The 
second volume Ls much larger and is 
simply titled TV Secrets Volume If 
tS24.95). Henry and ATVQ can be con- 
tacted via phone at (219) 662-6396; 
FAX at (219) 662-699 1 ; or by mail: 3 N. 
Court St* Crown Point IN 46307. 

You will find articles covering many 
ATV construction, operation and infor- 
mation topics, including Bill Brown 
WB8ELK s ATV column in 73. Bill 
takes on timely issues with insight 
on the latest gear and activities in this 
specialized niche of amateur radio, 

I hope you get started w ith ATV soon— 
and see what you've been missing! 




Photo E, HATS members John and Stuart 
Ross provide live coverage of the Houston 
Methodist Marathon via ATV 

73 Amateur Radio Today ■ July 1997 13 



Number 14 on your Feedback card 




to See What You Hear 



WARNING! This is easy! 



Ron L. Sparks KCSODM 

24818 Lakebriar Drive 

KatyTX 77494-1809 



Anyone can bypass the hurdles 
and jump right into having fun 
with ATV, The good news is that 
very few ATVers feel threatened by any- 
body, so getting started is really easy! 
Notice that I said "threatened," Our 
hobby is plagued by two problems 
which make it unnecessarily hard for 
newcomers. Some readers may be of- 
fended by my assessment of these prob- 
lems, but my objective is to make it easy 
and interesting for people to try out ama- 
teur television (ATV), I am not necessar- 
ily trying to be "nice/' By being aware 
of the problems, things will be easier for 
newcomer and Elmer alike. 

Both these problems arise from our 
strengths, so let's be honest about them. 
First, the strength and reliability that 
comes from a spread-out redundant, 
self-healing organization causes informa- 
tion to be scattered and disorganized. Sec- 
ond, the technical expertise and practical 
know-how that create a unique member- 
ship often cause "outsiders" to be forced 
through barriers designed {subconsciously. 
I hope) to protect the "insiders." 

If you want to test the second point, 
just pick a tight between the "outside" 
and the "inside" by honestly asking, 
"Why?" Then sit hack and listen. A 
simple equation can be used: The vol- 
ume and duration of the ensuing argu- 
ment equals the strength of the threat the 
inside" defenders feel. Typically; the 
more threatened they feck the more arbi- 
trary and difficult the hurdles to joining 
will become. 

Five simple steps 

I. Develop curiosity: The first step is 
to decide you are interested and begin 
looking at your options. The particular 
14 73 Amateur Radio Today • July 1997 



ATV avenue you choose to explore de- 
pends on your personal interests. Do you 
want to help a specific charity or organi- 
zation with your skills? Do you want to 
aid in emergency response? Do you 
want to create a different view of the 
world by seeing from the level of your 
pet, your radio-controlled model, or the 
top of your antenna tower? Do you want 
to monitor some area remotely? Would 
you like to have a "looky talky"? Would 
you like to create a network of mobile 
cameras for traffic monitoring? Do you 
want an inexpensive way to experiment 
with microwaves? Arc you wanting to 
try something really exotic like ATV via 
satellites? Do you want to see what the 
other ham is talking about? 

2. Finding where you arc: The next 
step is to find out where you are — in 
both a physical sense and from an equip- 
ment standpoint. One sidebar is a list of 
areas with activity in ATV. All of these 
areas are shown to have ATV repeaters 
and the list is growing daily. If you are 
not in an area covered by a repeater, do 
not give up. There is plenty to do even 
without repeater access. While you are 
checking the activity in your area, don't 
forget your local ham clubs. Most of the 
people in these clubs are willing to point 
you toward others with similar interests. 
There are even some clubs which are 
specific to ATV In the Houston, Texas, 
area, HATS (Houston Amateur TV Soci- 
ety) is very active and devoted entirely 
to ATV. If you arc already licensed, you 
have probably made the necessary con- 
tacts through the testing process, exist- 
ing club, or local repealer. You just need 
to ask them about ATV. 

If you are not yet licensed, this is 
where the first principle I mentioned 



earlier becomes a difficulty. It is often 
hard to find a club if you do not already 
know of one. Most clubs have a limited 
budget and operate by volunteer efforts. 
As a result thev have limitations on how 

■r 

much general publicity they can do. A 
way to find them without Internet access 
is to contact the ARRL at I -800-32 
NEW HAM (HOO-326-3942) and ask 
them for contact information on Volun- 
teer Examiners (VEs) in your area. 
These VEs will almost always be con- 
nected with a local club. Thev will also 
be interested in explaining how to go 
about getting licensed. By attending one 
or two club meetings, you will make the 
contacts you need to find the ATVers in 
your area as well as other ham informa- 
tion you may be interested in. If you are 
new to a club (even if you are not new to 
electronics or ham radio), be prepared 
for the second principle 1 mentioned to 
rear its head. Many club members have 
been in the organization for a long time 
and they forget how intimidating a room 
full of stony-faced strangers can seem to 
a newcomer. Just keep in mind that they 
enjoy the same thing you do or they 
wouldn't be there. Don't take the ty I 
thought everybody knew that" comments 
as personal. They've been doing it so long, 
they really think everybody does know. A 
few honest questions will almost always 
open them up. One final tip: A wise friend 
told me ? "Repealers and ham clubs are a 
lot like your local bar or pub. Each has a 
different character of clientele. Move 
around until you find one that matches 
your personality — before long it will 
seem like a comfortable shoe." 

Licensed or not another good way to 
find ATV activities is by an Internet 
search. Increasing numbers of clubs and 



individuals are putting up Web sites. 
The thoroughness of this resource is im- 
proving rapidly. Two Uniform Resource 
Locators (URLs) that are good starting 
points are the HATS home page at [hup;/ 

/www.stevens.com/HATS/home.html] 
and the Southern California (WA6SVT) 
ATV repeater page ai [http://web.io- 
online.com/users/forsberg/atv.htm]. 
These pages have links to alot of ATV 
information and activities. The link 
pages can be reached from Lhe above 
URLs or directly at [http://www.stevens 
.com/HATS/sites.html] and [http://web 
.io-on line, coin/user s/fors berg/links, htm] 
respectively. If yotfre in need of general 
ham information or lots of links to good 
ham-related sites, you might want to try 
starling at [http://wwwxlarc.org/] or for 
those of you interested in what's going 
on in Europe, try [http://www.innoits 
. co, uk/~asperges/index2. html 1. While 
there isn't much in the way of ATV-spe- 
cific software, the famous Oakland site 
is a wealth of ham-related information. 
You can enter at the ATV directory by 
using [http://oak.oakland.edu/pub/ham 
radio/dos/digital/atv/j. Just click on 
"Parent Directory" to move up and ex- 
plore the whole ham radio tree. There is 
a file index al the IIAMRADIO direc- 
tory. Now that you know where the 
people, repeaters, and software are, it's 
time to jump in. 

3. Planning where to go: The abso- 
lutely cheapest means to try out ATV is 
with a Receive-Only (RO) setup if you 
live within 25 miles or so of a repeater 
site. Most of you probably already have 
all the equipment and know-how it 



takes. Table 1 shows thai lhe 70cm ham 
band, often used for repeater output, can 
be received on cable-ready TVs or 
VCRs. Check the repealer directory or 
with your local club, and see if they are 
on one of the channels shown- If so, you 
can rig up an RO setup in 15 minutes. 
Just connect a good UHF antenna to the 
antenna input of your cable-ready set, 
but put it in the Cable-Ready mode. 
Then tune to the proper cable channel 
and you should see the repeater. Some 
people in the Houston area are even able 
to do this with rabbit ears! One note, 
however: Cable converter boxes will 
probably not work in this application. 
They are general ty designed for the 
high-leveJ signal from the cable and are 
not sensitive enough to work with an 
antenna. 

You may need to experiment with 
whether to place the antenna horizon- 
tally or vertically. This depends on the 
repeater antenna polarization. Here in 
Houston, the output is horizontal and the 
input is vertical. That may be pretty 
common because it allows normal yagi 
or TV-style antennas to be placed nor- 
mally (i.e., parallel to the ground) for re- 
ceive, The transmit antenna back to the 
repeater can then be a vertical whip 
(great for mobile use). 

But what about the antenna? That's 
not a problem either. The antenna can be 
a surplus UHF TV antenna, or you can 
build your own. I went the simple route 
and bought a kit from HATS for $ 15. As- 
sembly took 20 minutes. It's giving me 
snow-free pictures even though it's 
mounted inside mv attic and located 24 



miles from the repeater. That $15 repre- 
sents my total investment in getting 
started. 

4. A piece at a time: The thing to re- 
member is that this is a hobby. The fun is 
in the doing, not so much in the finish- 
ing. ATV is a great way to enjoy this 
hobby because il lends itself to little 
steps. For example, once you're receiv- 
ing the local repeater you'll want to par- 
ticipate in any nets held there. This will 
usually take only a 2m handie-talkie 
(HT). There are now quite a few of these 
priced under $200 new. The local 
AM SAT Net is held here in Houston on 
2m and is simulcast on the HATS ATV 
repeater. It is a real improvement to get 
to watch the net rather than just listen. 

The addition of the 2m rig allows ac- 
cess to the control functions of the ATV 
repeater, letting the newcomer experi- 
ment with switching cameras, changing 
audio input, etc. Once you're comfort- 
able with this, you will want to get on 
the air, A cheap way to experiment is to 
locate a source for the Rabbit™ trans- 
mitters thai were frequently offered at 
discount department stores. 

The early variety of units operated in 
the 900MHz ham band, and will allow 
you to experiment with different anten- 
nas, camera types, audio mixers, tillers, 
and other aspects of ATV A camcorder is 
a readily available input device. Many 
older camcorders, especially ones with 
broken tape mechanisms, can be found 
at garage sales, pawnshops, and repair 
facilities almost for free. Photo supply 
mail-order firms often have very good 
prices on simple tillers. 



Cable Channels in the 70 cm Ham Band 


Cable-Ready 

Tuner 

Channel 


Lower Edge 

of Band 

(MHz) 


Upper Edge 

of Band 

(MHz) 


Video Carrier 

Frequency 

(MHz) 


Color 
Subcarrier 
Frequency 

(MHz) 


Sound 
Subcarrier 
Frequency 

(MHz) 


Cable TV 
Band Name 


57 


420 


426 


421.25 


424.83 


425.75 


Hyper 


58 


426 


432 


427.25 


430.83 


431.75 


Hyper 


59 


432 


438 


433.25 


436.83 


437.75 


Hyper 


60 


438 


444 


439.25 


442.83 


443.75 


Hyper 


61 


444 


450 


445.25 


448.83 


449.75 , 


I Hyper 



Table /. Cable TV is on the ham hands 



73 Amateur Radio Today • July 1997 15 



When you feel comfortable with these 
aspects, you can jump up to repealer input. 
Things may be a little different for those 
repeaters with 420MHz or 900MHz input, 
but the principles will be the same as you 
need for the 1280MHz repeaters. One of 
the big advantages of the higher- frequency 
inputs is the smaller size of the antennas 
required, 

5 + Keep it up: The last step is the real 
key. As you can see from step four, the 
possibilities are limited only by your 
imagination and desire. As with any new 
endeavor, you must keep looping back 
to the curiosity step, then progressing 















r _l_l_ 








\ 


Satellite Receiver "feri 75MH/ 

1 1 \ i« Loop 1 






1 1 












H/v in 




^^^B 


VV5PZP 








■V- ■':• j H H 




■■. . . ".-.'• .."«■"■-■ 




















Pre -Amp 










Channel 3 or 4 

















Fig, /, Microwave ATV on the cheap. 

forward with a new aspect or component. 
This loop is the source of the fun and 
amazement that ATV can generate. Noth- 
ing keeps you from going down several 



palhs at once, either Right now I am 
building a 1.296GHz version of the Kent 
Britain WA5VJB antenna to hook to the 
HATS arrangement shown in Fig, 1. I 



ATV 



Cable Box 



Cable-Ready 



Composite 
Video 



Downconverter 



DSB 



FSTV 



NTSC 



PAL 



SECAM 



VSB 



Glossary of Common ATV Terms 

Amateur television is often called ATV. Most often this means transmitting and receiving 
video and audio at normal speed. Sometimes called Fast Scan TV (FSTV). 

A cable box is a set top converter which allows signals outside the normal broadcast band to 
be downconverted to channel 3 or 4 for viewing on any TV. These are not usually sensitive 
enough to be used in ATV. 

A cable-ready tuner on a TV or VCR is designed to pick up signals outside of the normal 
broadcast band. 

A composite video signal is one which contains the base band video with the proper (i.e. 
NTSC, PAL f SECAM, etc.) synchronization pulses and color information. This will typically 
have a voltage peak of about 1 V and a bandwidth of 4,5 to 6 MHz. 

In tuning the ATV frequencies on a regular TV some form of down conversion is required. 
While this may sound complicated to a newcomer, it is probably built into sets that are cable- 
ready. 

Double Side Band is an extremely simple mode used for most microtransmitters. It is also 
wasteful of band and power. In all but the least expensive or smallest transmitters, the lower 
sideband is filtered out with a Vestigial Sideband (VSB) filter, Modern TVs will receive a DSB 
signal just as well as a VSB signal due to filtering in their IF sections. 

Fast Scan Television is a synonym for ATV. tt implies that the transmitted frame rate and 
scan speed are the same as those of an international standard. 

National Television System Committee is the group that set up the way TV is broadcast in 
America. Because of its vacuum tube heritage, it is often jokingly taken to mean "Never The 
Same Color" from the way color is encoded. The picture is transmitted at 59,94 fields per 
second with two interlaced fields of 262.5 lines making one frame. The line rate is 15.734 
kHz. 

Phase Alternating Line is the TV standard for broadcast in the UK, Central Europe, 
Scandinavia, Asia, Australia, and much of South America and Africa. It comes in several 
"flavors" such as PAL-I which affect the way the sound subcarrier is transmitted. The UK uses 
PAL-I. The picture is transmitted at 29.94 fields per second with two interlaced fields of 312.5 
lines making one frame. The line rate is 15.625 kHz. 

Sequentielle CouleurAvec Memorie is the French-originated TV standard that is used in 
France, Eastern Europe, Russia and the former Soviet states. 

Vestigial Sideband fitters are used in the transmitter to eliminate the lower sideband 
component. As with Single Sideband (SSB) phone transmission, this is the most power- and 
spectrum-efficient means of transmitting the signal. The main difference between a VSB and 
an SSB signal is that the carrier is still present in the VSB signal while it has been removed 
from the SSB signaL 



16 73 Amateur Radio Today • July 1997 



State or Country 



Web 
Page 



Alabama 




Alaska 




Arizona 


Yes 


Arkansas 




California 


Yes 


Canada 


Yes 


Colorado 


Yes 


Delaware 




District of 




Columbia 




Florida 


Yes 


Georgia 


Yes 


Germany 


Yes 


Great Britain 


Yes 


Illinois 




Indiana 




Iowa 




Kansas 




Kentucky 




Louisiana 




Maryland 


Yes 


Massachusetts 




Michigan 




Minnesota 




Mississippi 




Missouri 




Nebraska 




Netherlands 


Yes 


Nevada 




New Hampshire 




New Jersey 


Yes 


New York 




North Carolina 




North Dakota 




Ohio 


Yes 


Oklahoma 


Yes 


Oregon 


Yes 


Pennsylvania 


Yes 


Puerto Rico 




Rhode Island 




South Carolina 




Tennessee 


Yes 


Texas 


Yes 



Utah 
Virginia 
Washington 
Wisconsin 



Yes 



Yes 



ATV Activity Hot Spots 

City or Region 

Numerous areas 

Fairbanks 

Pinal Peak and Phoenix 

Little Rock, Harrison, Heber Springs, Russellville, Pine Bluff 

Numerous areas 

Numerous areas including Calgary, Winnipeg, Ottawa, Montreal, Regina, 

Saskatoon 

Numerous areas including Boulder, Colorado Springs, Denver 

Wilmington 

Alexandria VA; Rockville MD 

Numerous, some NASA-related 

Atlanta, Dalton, Savannah 

Numerous areas including Cologne and Lower Rhine/Dutch Border 

Numerous areas including East Sussex, Kent, West Devon, and Coventry 

Decatur, Champaign, Des Plaines, Gaiesburg, Peoria 

Numerous areas 

Davenport, Des Moines, Dubuque 

Kansas City, Topeka, Wichita, Pittsburgh 

Bowling Green, Elizabethtown 

Baton Rouge, New Orleans, Shreveport 

Annapolis, Baltimore, Rockville 

Boston, Leyden, Springfield 

Ann Arbor, Saginaw 

Minneapolis-St. Paul 

Gautier 

Columbia, Kansas City, Joplin, St. Louis 

Grand Island, Lincoln, Omaha 

Arnhem, Eindhoven, Soest, Ulft 

Pofosi Mountain 

Derry 

Brookdale, Moorestown 

Ithaca, Finger Lakes 

Charlotte, Greensboro, Shelby 

Harwood 

Numerous areas including Columbus 

Oklahoma City, Tulsa 

Portland 

Numerous areas, Carnegie Tech 

East 

Providence 

Lexington, Sumter 

Numerous areas including Johnson City and the Tennessee Valiey 

Numerous areas including Abilene, Austin, Beaumont, Dallas, Houston, 

The Woodlands, Clear Lake, Midland, Tyler, Waco 

Saft Lake City 

Numerous areas 

Western Washington 

Numerous areas 



73 Amateur Radio Today * July 1997 17 



have also put together a 7 -ounce micro- 
ATV system for launch in my brother's 
model rocket. You could be having as 
much fun as we are! This is one facet of 
the hobby where I can officially close 
with "1*11 be seeing you." 

References 

1. "Fast-Scan Television," The ARRL 
Handbook for Radio Amateurs, 73rd 
Edition. 

2. Ruh, Henry KB9FO, "The Nature 



of Video," CQ VHF - Ham Radio Above 
50 MHz, March & April 1997. 

3. Garcia, Fernando, "A Beginner's 
Guide to World Wide Television 
Standards," Nuts & Volts Magazine, 
December 1996, 

4. Valkenburg, Mac E., Reference 
Data For Engineers, 8th Edition, 
Butterworth-Heinemann, 1993. 

5. "Amateur Television/' The ARRL 
Repeater Directory, 24th Edition. 

6 . L<http^/www,usere.inierpi>it,net/- j bay 
/theatre~sound/tv-2.htxnl>]. This file has 



some very good information and was 
used to cross-check the Hyperband 
Cable frequencies, but it appears to have 
a minor error. When compared to Refer- 
ence 4, above, the frequency stated as 
"Picture Carrier" in this table is, in fact, 
the lower band edge. The "Picture Car- 
rier" or Video Carrier would be +L25 
MHz from this edge, not -L25. 

7. Britain, Kent WA5VJB, "Cheap 
Antennas," Houston Amateur Television So- 
ciety Flyer, HATS, Inc., 1 3054 Pebblebrook, 
Houston TX 77079, 1997. 




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18 73 Amateur Radio Today • July 1997 



Number 19 on your Feedback card 



C-Band Low Noise Amplifier 

Use discarded satellite receiver parts to soup up your ATV system. 



Rick Pense WD5BQN 

1511 Brtckarbor 

Houston TX 77449 

E-mail: [WD5BQN@stevens.com] 



In keeping with the amateur tradition 
of using the cheapest means possible 
lo accomplish results, I have as- 
sembled complete 1,2GHz receive sys- 
tems from old satellite receive 
equipment. The desired satellite receiv- 
ers are known as block downconverted 
receivers. In their original implementa- 
tion, they act as a tunable IF strip. The 
frequencies that they are designed to 
tune are 950MHz to 1450MHz. This 
makes them excellent candidates for use 
as receivers in our 1.2GHz FM ATV 
hand. The front end of these receivers is 
very broad, so simply attaching an an- 
tenna to them usually gives poor re- 
sults — you're weighed down with 
reception of broadcast TV signals, pag- 
ing transmitters, cell phone intermod, 
and other signals. Also, they aren't usu- 
ally very sensitive, so you have to add 
some type of preamp to bring the 
received signal up to the input level the 
receiver wants to see. 



The first problem, that of the undes- 
ired signals, is cured by using a 
waveguide transition made from coffee 
cans as an antenna. The design for this 
feedhorn is available in various books 
and magazines, but it's simple enough to 



cut the horn feed off and attach a type-N 
connector are okay if you've been around 
microwave equipment for a while, but I 
think it's time to give a more detailed de- 
scription so that others can enjoy the kind 
of fun we're having here in Houston. 



"We just ask homeowners with incorrectly-aimed dishes if we 

can have the LNA." 




EBBtth 






FhoioA. Two LNAs and a two-axis feedhorn, hot off a satellite dish. 



run through right here. Solder two 34.5- 
ounce coffee cans together so that only 
one end remains sealed. Place a type-N 
connector with a two-inch #14 wire sol- 
dered to the center pin three inches from 
the scaled end. You now have a lOdB 
"cantenna" to use in front of your receiver. 
The hardest part of this project was the 
preamp. High-gain, low-noise prcamps for 
use at I.2GHz are not cheap. I found a so- 
lution in an old copy of 73. C. L. 
Houghton WB6IGP, in his ''Above and 

Beyond" column 
{May 1993), de- 
scribed a conver- 
sion of old satel- 
lite LNAs (low 
noise amplifiers) 
for use as pre- 
amps on spectrum 
analyzers. These 
LNAs were used 
on the earlier- 
style TVRO satel- 
lite sy items and 
they were de- 
signed lo pass 3.7 
to 4.2GHz. His 
instructions to 




First, find an LNA 



The LNA is easily identified by the 
type-N connector on one end. Wc have a 
lot of luck finding these LNAs around 
Houston: We just ask homeowners with 
incorrectly -aimed dishes if we can have 
the LNA. if they aren't using the dish 
(see Photo A). Sometimes the owner 
says yes, but only if we take the dish — 
which is fine — these dishes perform 
well at 1.2GHz. I have a six-footer on 
my van, with a cantenna feedhorn, 
which has worked our repeater from 
numerous special events locations. 

Place the LNA in a vise and carefully 
cut off the waveguide input section, 
leaving an area to mount the type-N 
connector (see Photo B), Remove the 
screws which hold the cover on the 
preamp. If a circulator/ isolator is in your 
preamp, it must be removed. Look 
around inside the preamp to see how the 
unit was originally assembled. It may 
be necessary to remove all the screws 
and unsolder and remove the type-N 
connector to get the isolator out. The 
isolator must be removed as it is a 
narrowband device and we are moving 
73 Amateur Radio Today • July 1997 19 




Photo B* Waveguide has been sawed off. 



the designated passband down quite a bit 
(see Photos C and D). With the isolator 
removed, reassemble the preamp and 
mount a type-N connector near or in 
the hole where the original 3.7GHz 
waveguide probe was. Use either mini 
hardline or double-shielded mini coax to 
connect the type-N connector to the 
preamp's input* When you place the 
connector and its mounting be sure it's 
sealed watertight, because the LNA was 
designed to be mounted outdoors, and 
it'll take a beating from the elements. 
Both the center conductor and the 
shields of the coax must be attached to 
prevent oscillation of this very high-gain 
device. These units have an advertised 
gain of 40dB, and we have measured 
one device which had 60dB of gain with 
a 2,5dB noise figure after modification. 

At the other end of the preamp, a comb 
filter may be included to limit the pass- 
band of the preamp. Removal of the filter 
is accomplished with a hobby knife. Only 
the tips are left, and a wire jumper is in- 
stalled across them to try to keep stripline 
integrity (see Photos E and F). 

You tweak the amp (if necessary) by 
removing or relocating blocking capaci- 
tors on the strip! ines. Older- type amps 




Photo C. Circulator to be removed. 




Photo B. Circulator removed and coax 

installed. 



have two blocking caps on the 
microstriplines which decouple the 
stages in the preamp, Removal of the ca- 
pacitor nearest the GaAsFET electrically 
lengthens the microstrip, lowering the 
operating frequency. Be careful to pre- 
vent oscillation, as these are very low- 
noise, high-gain GaAsFETs in these 
amps. Generally, amps with five or more 
active devices should not be tweaked, 
Amps with three or four stages can 
be heavily massaged to lower their oper- 
ating frequencies. Coupling capacitors 
between stages can be increased to aid 
low frequency response, Usually, while 
tweaking, I will simply add a capacitor 
beside the original in case removal is 
required later. Tweaking is a trial-and- 
error approach, and should not be a 
substitute for proper preamp design, 





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Photo E* Comb filter to be removed. 




Photo F. Comb fitter bypassed with wire 
jumper. 



When completed, the modified preamp 
is a gain-block type of device. It should be 
very broadband, very sensitive, and fairly 
quiet. Use on oiher bands or modes is pos- 
sible — Phase 3D comes to mind. The same 
requirements for frequency selectivity 
mentioned about the satellite receivers ap- 
ply lo these LNAs. Some type of fre- 
quency-selective filtration must be applied 
in Irani of the amp. Use of a commercial 
1,2GHz yagi directly into the preamps was 
unsatisfactory. 

We've had some success in Houston 
with a two-cavity filter which allows full 
duplex operation on L2GHz. Separate 
antennas and careful placement are re- 
quired. We transmit on L255GHz and 
receive on L285GHz. The use of these 
satellite receivers, only 30MHz removed 
from 18W transmitters, has proven them 
a practical substitute for much higher- 
priced commercial FM ATV receiver 
systems. 




Photo G. Cantenna and preamp ready for 



service. 



20 73 Amateur Radio Today • July 1 997 



Number 21 on your 



card 



Video Titlers for ATV 



If you're serious about ATV, a video titter is the way to go. 



Fred Juch N5JXO 

13054 Pebblebrook 

Houston TX 77079 

E-mail: [N5JXO@stevens.comJ 



n the 10 years Fve been involved in 
amateur television, I've used just 
__ about every type of station video 
identification scheme possible, I began 
with an old Vidicon camera with an on- 
screen titlcr. I've used posterboard in the 
station background. I have even tried 
CGA computers to generate the proper 
ID screens. All work fine, but..* 

A video titter will overlay your video 
screen with text information. Similar to 
national news broadcasts, you can put 
your ID in the corner of tbc screen, or 
you can use scrolling or crawling text. 
The units reviewed here are the low end 
of the current consumer market. They 
are intended for home video editing or 
adding titles to home movies. If you put 
a video titler as the last device in the 
video line before your transmitter 



you will always be able to send your ID 
independent of your video source. 

You can spend hundreds of dollars 
(the Videonics Titlemaker 2000 runs 
about $650), but the three most popular 
(in the ham community) titlers under 
$150 are the Sirna ColorWriter Mag- 
ic ($139.95 at this writing), Sima 
ScreenWriter ($99.95), and the Ambico 
V-6350 ($119.95). All are available via 
mail order. 

They have very similar features and 
performance, All have memories, can 
crawl text across the screen (right to left), 
and scroll text up the screen. They differ in 
the number of colors, amount of memory, 
and font sizes. I know hams active in ATV 
using all four titlers mentioned above and 
each would tell you theirs is the best for 
their specific application. 




Photo A. Video titlers come in different shapes and sizes, 



All three tillers evaluated below run 
on 9 volts DC from a wall transformer. 
Each has a 7805 voltage regulator in- 
side, so they should run off 13,5 volts if 
you take care to add a heat sink to the 
internal regulator (for portable use). The 
keyboards have rubber keys, and support 
special characters for international lan- 
guages. AH are in plastic cases although 
the Ambico V-6350 has a metal baseplate 
(the heat sink is not connected to that plate, 
however)- S-video inputs and outputs are 
also standard on all but the ScreenWriter, 
and the Sima units are available in PAL 
as well as NTSC models. 

I bought and/or borrowed each of 
these titlers, and evaluated them to find 
the best features of each. All operated as 
the manual said they should. After get- 
ting familiar with each unit I was able to 
quickly create ID screens and use the 
special effects like a professional. Here 
is an in-depth look at each unit and how 
it operates. 

Sima ColorWriter Magic 

The ColorWriter Magic is the largest 
of the titlers, measuring 13.75" x 8.5" x 
2.5" high, It has 13 screen memories, a 
standard-size keyboard, and boasts eight 
colors. For battery backup of memory 
two LR44 button batteries are included, 
and are stated to last six months. This is 
the only unit (of these three) with a full 
size keyboard, so there is a lot of empty 
space in the unit for home-brew pro- 
jects. (Maybe a VOR timer circuit?) The 
ColorWriter treats text and special 
effeets separately. The only data in 

73 Amateur Radio Today • July 1997 21 



^m 



memory is the text and color data. 
To create output the operator selects 
the page of memory, then what effect 
is desired, then "Insert/ 1 The last two 
screens of memory are reduced text 
pages and are used with the zoom fea- 
ture. One page is a Headerline that can 
he displayed along with any other 
screen. The Headerline is great for 
putting your callsign on screen, while 
you scroll through other information 
simultaneously. 

The colors (black, red, green, yellow, 
blue, magenta, cyan, white) are selected 
on the special section on the keyboard 
labeled "Color Select." There are five 
variations possible with these colors, in- 
cluding colored letters, boxed letters, 
bordered letters, reversed letters, and 
colored background. The boxed letter 
looks like a square of any color, with the 
letter in it, also of any color. Bordered 
letters are letters of one color outlined 
with another color I usually outline with 
black for clarity, A neat trick this unit 
will do is reversed letters* That's not the 
same as backwards letters — if you select 
a color, then select reverse, the outline 
will be the color selected and the letter 
will be transparent — a neat effect for a 



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callsign. All six colors are available in 
any combination. 

When you select a memory location, 
then press "Create/' the screen fills with 
small squares for editing. You can select 
colors, background, etc., and then start 
typing. The special colors can be edited 
later, one character at a time. The big- 
gest annoyance is the lack of word wrap. 
You have to hit return at the end of each 
line. If you edit a page you may have to 
retype the entire page to add text at the 
top of the page. The editing keys allow 
you to adjust one of four character sizes 
for the entire page only; one of four 
scrolling speeds; and basic move/add/ 
delete functions. 

The insert keys allow the basic func- 
tions of inserting your screen on top of the 
selected video. You can do this in several 
ways. One function is fade in or out Oth- 
ers are the scroll-up screen, and scroll 
across the bottom of the screen. Two of the 
memories support a zoom feature. This 
stunt is so cmde it should not be consid- 
ered a feature. It places text in the center of 
the screen, then enlarges or reduces the 
font size to simulate zooming in or out, but 
the font sizes are not proportional, and the 
t results are awkward* 

The special effects section of the key- 
board allows you to move text onto or 
off the screen in one of six special ways: 

• The entire screen can be brought into 
view from the right side of the screen. 

• Alternating lines can be broughl onto 
the screen from opposite sides of the 
screen. 

• Lines can be brought onto the screen 
from the right, one line at a time, 

• Text can be scrolled down the screen 
from the top. 

• Text can be entered as if typing on 
the screen, one character at a time. 

• Text can be scrolled up from the bot- 
tom. This is the best feature of the spe- 
cial effects section of the keyboard, as it 
makes text exit as well. For example, 
you can make the text enter from oppo- 
site sides of the screen. It will stop when 
text is all on-screen. You can then select 
"scroll up," and the text will slowly 
move up the screen until it is gone. The 
horizontal motion moves in jumps, one 
character space at a time, but the vertical 
scrolling is very smooth. 

The ColorWriter is very versatile, and 
has enough features for creative ATV use, 
The colors can be mixed to produce 



exciting and brilliant on-screen text, The 
drawbacks are no flashing characters and 
only one available font. The special fea- 
tures will appeal to anyone who will be 
using this unit to put titles on tape for later 
viewing or transmitting. I also found the 
special effects fun to play with while 
transmitting over the local ATV repeater. 

Sima Screen Writer 

The Screenwriter is the smallest litler, 
measuring in at I1.5 n x 4" x 1.5" high. 
The memory is backed up with a single 
CR2025 or CR2032 battery, and should 
last one year before replacement. It also 
has 15 memories, three of reduced size 
that are reserved for the Zoom feature. 
Also the Screenwriter only puts out 
white text. This unit does have a demo 
mode that is activated by pressing the 
"Down" key after you power on. 

This unit is operated like the 
ColorWriter discussed above, with a few 
exceptions. The tioit cannot create a 
backdrop to put text on; you must have a 
video source connected to use it. The 
text can't be set on a block background, 
outlined, or reversed- There is one font, 
with four font sizes, so the keyboard is 
very simple and straightforward, 

« Create: In the create section of the 
keyboard you have keys to select page 
number, font size, and the editing func- 
tions (add, delete, line shift)- These 
will allow the entry of data into the 
memories for later viewing. 

* Insert: The insert keys allow a 
memory screen to be displayed over in- 
coming video. The limited functions avail- 
able are Zoom In, Zoom Out, Scroll Up, 
Scroll across the bottom of the screen, and 
Cut in and Cut out. One amazing discov- 
ery is that the Zoom feature actually 
works! And it works on Zoom in and 
Zoom out. The reason it works is that the 
fonts are more proportional than on the 
ColorWriter. Only memories 13-15 can be 
used with the Zoom feature. 

The Screenwriter can add a callsign to 
a screen very nicely, for a small unit. It 
can also scroll text across the bottom of 
the screen, or up the screen. I think of 
this unit as a good tool that will get the 
job done, but with no bells or whistles. I 
also missed the Headerline feature avail- 
able in the ColorWriter. If you are going 
to attach a unit to the handlebars of your 
bike, or on a portable camera, this may 
be the unit for you. 




Photo B* Sima ColorWriter screen with Charlie Keng N5XGW (right) shows Headerline at 
top with larger size text in center, all outlined in black. 



Ambico V-6350 

The Ambico is a slim 10J" x 6.5" x 
2 n high and has 10 pages of memory; 
for battery backup of memory, two AA 
batteries are needed. The V-6350 can 
generate eight colors, but only four at 
a time. 

The Ambico V-6350 has an adjust- 
ment knob on the back to set the width 
the image takes up on the screen. This 
allows the text width to be set so that it 
stays in the screen's viewable area. The 
"Mode" key is used to select how text is 
entered, manipulated through the use of 
special effects, and displayed or played 
back. This unit, like the Screen Writer, 
has a demo mode to help you learn what 
can be accomplished with the tiller, but 
the philosophy here is a little different. 
The memory not only holds the text, 
but also holds all the text manipulation 
information. This is very similar to 
making a small movie containing 
information and actions. 

• Edit: To start entering text, first 
select "Page/' then through 9. Now 
choices can be made by selecting op- 
tions on the edit screen. The background 
can be video, or solid white or black and 
is selected with the "Background" key. 
The flashing cursor indicates the color 
of text to be entered. Pressing "Color" 
will select one of the four colors shown 



in the color selection boxes on screen. 
Pressing "Shift" and "Color" will allow 
changing the colors in the four color-select 
boxes. The end result is that only four of 
the possible eight colors can be used on 
any one screen. Size is set for each line 
individually, and has four settings. 

The text borders can be set to solid- 
color, color-filled outline, or hollow out- 
line (transparent characters). Two fonts 
are available: one called normal, and one 
called narrow. The narrow font has only 
upper case characters. Unlike the other 
units mentioned above, the V-6350's 
characters can also be set to flash. 

• Effects mode: After the text is cre- 
ated (in edit mode), pressing the mode 
key moves the unit to effects mode. 
There are four ways text can be brought 
on screen: cut in; scroll in; crawl along 
the bottom of the screen; and wipe in. 
Wipes can be from top, bottom or cemer of 
the screen. A delay of up to eight seconds 
can be included before the text exit effect 
is performed. The exit effects are: cut; 
scroll out; and wipe off. Again, wipes can 
be: from top and bottom; from the bottom; 
and from the top. Three speeds can be se- 
lected with most effects. One caveat, how- 
ever, is that the V-6350 can't scroll in and 
scroll out on ihe same page. 

• Active mode: To play back the text, 
the "Mode" key is pressed again to reach 
"Active" mode. Here the memory pages 



can be played back like small movies, 
individually, or in an automatic mode 
that goes sequentially through the pages. 

The Ambico V-6350 does a good job 
of putting color text on the screen, The 
playback mode allows pages to be 
played back in a smooth predetermined 
method. The small size makes it good 
for cramped shacks or field work, but I 
was disappointed with the lack of back- 
ground colors and the limited color se- 
lection. Also you have to fully program 
all aspects of a memory page before 
playback is possible. Another drawback 
is that the Ambico drops off-line if the 
overlaid video is interrupted, This could 
be a problem if the input is switched be- 
tween non-genlocked sources. But at 
this price it can easily fit into most 
ATVers' budgets. 

Although all the units reviewed pro- 
vided good quality text on a stable video 
source, all got the wiggles if (he source 
was much less than perfect. And none 
had the ability to loop on an action, such 
as scrolling an information message 
over and over. The Headerline feature of 
the Sima ColorWriter was nice, but the 
Ambico is the only unit that offers flash- 
ing text. I believe the Sima ColorWriter 
is the most versatile titler. With the 
Headerline feature it offers a stationary 
text line while other text is scrolled or 
crawled across the screen. 

Still, any of these tillers beats a piece 
of cardboard on the wall for passing in- 
formation. All have been in operation for 
at least six months and are still working 
flawlessly. Are you old enough to re- 
member the old RTTY pictures made 
with text? With these tillers you can save 
the pictures in memories and recall them 
whenever you want. It's time to break 
away from those old graphics and put 
a polish on ATV shacks around the 
world! 




VfSA 



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Brj pn&ee am* spgcdnjiicra &e auHjad 10 ensign wittio-ji notes 



CIRCLE 167 ON READER SERVICE CARD 

73 Amateur Radio Today * July 1997 23 



73 Review 



Number 24 on your Feedback card 



Dr. NiCad Battery 

Conditioner/Rapid 

Charger 

Ramsey Electronics Model No. DN-1 



Mark L Meyer WU0L 
14153 West First Drive 
Golden CO 80401 









—■ — - ' — 










I 



DN-1 PARTS FINDER 




Photo A. The Ramsey Dt\ NiCad kit {ail 
photos by author). 



How many NiCd batiery packs do 
you have sitting around the shack? 

If you're a typical ham, the answer is prob- 
ably at least two for the handheld and 
several more for various pieces of equip- 
ment — and maybe a tew for assorted tools, 
toys, etc. I started looking around and 
counted half a dozen at this QTH. Some of 
the packs were functional and some were 
dead: but even the dead ones are too 
expensive to throw out. 

So what do you do to charge all those 
batteries'/ Are you charging them cor- 
rectly? NiCds should occasionally be 
nearly fully discharged and then fully 
recharged to keep them in good condi- 
tion. Arc you doing that? Is your wall 
recharger overcooking your batteries 
when they are connected for weeks on 
end? What about those dead batteries — 
can you restore them? 

Enter Dr. NiCad 

The good doctor can handle all these 
chores for you, plus provide fast charg- 
ing for your batteries — -without over- 
cooking them. The doctor is available 
from Ramsey Electronics in kit form or 
fully assembled- If you order the kit, you 
can get the basic circuit board and parts 
only. An optional case set can be ordered 
to go with the internals. 

The heart of Dr. NiCad is the 
Benchmarq BQ2003 chip specifically 
designed for NiCd charging, It is 

24 73 Amateur Radio Today * July 1997 



programmed by external jumpers on the 
board and switches to sense how many 
cells are to be charged, what charge rate 
is to be used, what discharge rate is to be 
used, and how long the pack should be 
charged. The chip senses the correct 
points to discharge the cells to, at what 
point to start/stop the quick charge, au- 
tomatically provides a "topping off* 
charge and then "tops off the batteries 
periodically. It also Hashes an LED in 
various sequences to tell you what is 
happening. 

I got interested in Dr. NiCad when I 
built a new QRP transceiver. For battery 
power, I connected two 7.2V NiCd 
packs together to make a 14.4V pack. 
The 7,2V packs are commonly used in 
video camcorders. My packs were rated 
KOOOmAh (milliamp hours). A 7.2V 
pack contains six individual cells in se- 
ries, so I had 12 cells connected in se- 
ries. The rated pack voltage divided by 
1.2 gives you the number of cells in the 
pack, 

Most packs used in handhelds contain 
from six to 10 cells (some contain 11). 
NiCds for toys and tools may contain 
from only one cell to several. As ex- 
plained above, I wanted to charge 12 
cells. As supplied. Dn NiCad can handle 
from one to 10 cells but it is easily modi- 
fied to handle more cells. The number of 
cells to be charged must be set in the unit 
by toggling the individual switches on a 
"DIP' 1 switch unit on the circuit board. 



Since I wanted to charge more than 10 
cells, and I wanted to be able to change 
the number of cells lo be charged from a 
front panel switch, I modified the unit as 
described below. 

Kit parts and assembly 

I ordered the basic kit, consisting of 
the PC board and the parts to stuff it 
with. The kit comes in a large plastic bag 
containing the instruction book, a couple 
smaller bags with the parts, large sche- 
matic diagram of the unit, and a large 
parts placement diagram. 

The instruction book is well done. In 
addition to showing you how to put the 
parts together, it gives a fairly detailed 
explanation of the process of charging 
NiCd batteries, a troubleshooting sec- 
tion, and a question-and-answer section 
about operation of the unit. The actual 
assembly portion has a check-off table 
for each part; this, combined with the 
parts layout drawing, makes it very diffi- 
cult to err in putting the kit together 

The circuit board is high quality and 
silk-screened with the parts layout. The 
parts were all present and were high 
quality although some appeared to be 
surplus as the leads were clipped. Every- 
thing fit and assembly went smoothly. 

The heat sink for the transistor that is 
used to discharge the NiCd packs ap- 
peared to be undersized lo me, espe- 
cially since I wanted to use a 12-cell 



pack. I beefed this up by bolting on addi- 
tional aluminum strips. Also, no heat 
sink compound was supplied to apply 
between the transistor tab and the heat 
sink (I added a dab I had on hand). No 
lockwashers are provided (I used my 
own). 

Modifications 

As mentioned above, I wished to 
charge a 12-eelI pack. The unit as pro- 
vided is designed to charge up to 10™cell 
packs. How many cells are to be charged 
is determined by a series string of 47k 
resistors. This is a voltage divider string. 
The switches on the circuit board (SI :1— 
9) merely short out the correct number 
of resistors as desired. If only one cell is 
to be charged, all the resistors in the 
string are shorted out except one (hence 
the nine switch positions on SI), This 
one resistor is permanently left in the 
circuit as designed and cannot be 
shorted by the switches, as explained in 
the instruction book. 

To modify the unit for 12 cells, two 
additional 47k resistors must be pro- 
vided, plus two additional switch posi- 
tions. I elected to use a front panel 
switch instead of the circuit board- 
mounted DIP switch that contained the 
nine indi vidua] switches for shorting the 
resistors. I used a 12-position rotary 
switch available from Radio Shack™. I 
also mounted all the switched resistors 



(now 1 1 47k resistors instead of nine) 
right on the switch tabs instead of on the 
board. This way only two wires go IVom 
the new switch to the board — one from 
the arm of the switch, and one from the 
top of the resistor string to the board 

(Fig. 1). 

The DIP switch also contained one in- 
dividual switch (SI: 10) to set the dis- 
charge rate. When this switch is closed, 
a low discharge rate is selected. When it 
is open, a high discharge rate is selected. 
I decided a low rate was appropriate for 
all my uses, so I simply jumpered 
(shorted) the SI: 10 holes on the board. 
Using an additional front panel switch 
for this function would make it select- 
able but I didn't choose that option, 

I provided my ow r n case. My case 
setup didn't allow for the use of the "on- 
off" power switch (S3: A) provided on 
the circuit board or the "discharge ini- 
tiate" switch (S2). also provided on the 
circuit board, I didn't use the switch pro- 
vided; I simply brought wires from the 
appropriate holes on the circuit board to 
the switches I provided on the front 
panel of my case. The "on-off* switch is 
just a normal toggle switch but the "dis- 
charge initiate" switch is a momentary 
push-button switch. 

Setup 

As mentioned above, the discharge 
rate can be set at a low rate of 140mA or 



a high rate of 280mA. I decided the 
low rate of 140mA would be fine for 
nearly all use. The low rate reduces the 
heat dissipation of the current pass 
transistor and the only disadvantage is 
that it will take longer to discharge 
than the higher rate. Set the low rate 
by closing switch SI; 10, or by short- 
ing the switch position with a jumper 
wire as described above. 

The charging current rate can be set at 
250mA, 500mA, or I A by positioning 
several jumpers on the circuit board. The 
instruction book explains how to calcu- 
late the best setting for your pack and 
then how to set the jumpers. I decided 
the 500mA setting would be line for my 
packs. This too could be set up by 
switches to make it selectable but would 
be a little complicated. I used jumper 
wires as described in the book. 

The charging time-out feature is also 
set up by jumpers. The instruction book 
tells you how to select the correct time 
(180, 90, 45, or 23 minutes) for your 
pack and set the jumpers. I selected 180 
minutes for my application. 

Power supply 

The unit, in kit form or fully as- 
sembled, does not provide a power sup- 
ply for charging your NiCds. It is the 
controller; you must provide a regulated 
source of power for the unit. The 
instructions recommend a "regulated" 



47K^ 



47K 



47K 



47 K 



New 12 Pos, Sw 
Replacing S1 



47K 

Eleven 11 47k Resistors 
ir\ p face of original nine 





47K 



47K X3 



*R23 
47k 

!VW 




*R1 
1k 



47k 



To 

*l_1 t *Q3 V 



? 



i? 



+v 



*R2 
10 



47K Shown in position 
to charge 4 cells 



* Indicates Un modified Dr.NiCad 
Part on Circuit Board 



R24 
471 



Fig. 1. Modifications to accommodate 12 cells, 



73 Amateur Radio Today ■ July 1997 25 




Photo B, The interior, with mollifications. 
Note the extra aluminum strips Ixdred 10 the 
heat sink of the discharge transistor 1Q.I1. The 
power supply board is mounted below the Dr. 
NiCad Iward with the rransfonner to rear. 

supply between 12 and I4VDC capable 
of at least 1.5A. Most hams have such a 
supply in the shack already. 

I wanted to have the power supply 
and controller all in one case, I also 
wanted to charge up to 12 cells, so I 
decided I would need to provide a 
slightly higher voltage. The instruction 
book indicates some problems can be 
encountered when too high a voltage is 
utilized with a low-voltage battery 
pack. With this in mind. I decided to 
build a supply that could provide a 
high or low voltage depending on what 
I intended to charge. 

The circuit in Fig. 2 shows the power 
supply circuit. It will provide approxi- 
mately 1 1 V in the "low" position and 
18V in the "high" position. The regula- 
tor chip, U I, should be a LM3I7T. The 
"T" indicates the capability of I.5A. 
This is in the full-sized TO-220 case 
rather than the "MP" series with the 
smaller tab (rated 0.5A). Use a heat sink 
with heat sink compound on U I . 

The transformer should be rated ap- 
proximately 18V at L5A. I used a 24V 
transformer (from my junk box) with 
some secondary turns removed to bring 
it down to about 20V, Radio Shack™ 
273-1515, rated at 18V and 2,0A would 
be ideal If yuu won't be charging a pack 



of more than ten cells, the Radio Shack 
12V. 2 A transformer (RS 273-1511) will 
do the job for TL In this case you will 
not need the switch or R3. R2 should be 
replaced with a 2.0k unit, which should 
result in a power supply delivering ap- 
proximately 12V. If the 2.0k resistor is 
increased slightly in value, the voltage 
will increase correspondingly. 

My unit worked great when I fired it 
up I charged up (and discharged) sev- 
eral packs, then tried a pack thai was 
"dead," By cycling the pack several 
limes over a few days, as described in 
the instruction book, the pack was 
revived! 

1 tried another "dead" pack. No matter 
how many times I tried cycling, this 
pack remained dead. Three cells out of 
seven seemed to be shorted. Then I tried 
an old trick of applying a heavy dose of 
current to the three shorted cells. I very 
momentarily applied a full 12V from a 
lead-acid battery to each individual cell. 
This seemed to cure them. Then 1 cvcled 
them several limes with the good doctor. 
Presto! — another pack restored. Cau- 
tion; If you try the heavy-dose-of-cur- 
rent trick, be very careful! Cells can 
rapture. Use long leads — and place the 
cells and battery around the corner, or 
behind something, so you're out of the 
line of fire should one blow up. 

I am very impressed with Dr, NiCad. 
This is something thai should be in ev- 
ery shack. My unit has paid for itself al- 
ready by restoring two dead packs — and 
I expect many more years of service 
from the good "Doctor." 

The Dr. NiCad kit (DN-l @ $49.95 
for the kit only) is available from 
Ramsey Electronics, Inc., 793 Canning 
Parkway, Victor NY 14564. 

The modification parts I used are; 

SW1 - Single Pole, 1 2 position. Radio 
Shack #275-1385 

T 1 - Radio Shack #273- 1515 



^r- 



01-01 

2A,50V 



11S VAC 




Tl: 1 16VAC pri 

1SVAC®15As*x 

(See Text) 



U1 
LM317T 



20D0uF 

50V -r 



R2 
3.3k 



R1 

2*0 



0.1 + 



2uF 



0(*J 



1k 



DC, to Or NiCad 



HI A 



LO 




^ i 2W 



■O (-) 



Fig. 2. Dr. NiCad power supply. 

26 73 Amateur Radio Today • July 1997 




PhotQ C The finished project, 

D4 - One 2 A, 50V bridge unit or four 
RS-276-1661 (3A) 
Ul -LM317T(Digi-Key) 



Never sry die 

Continued from page 5 

need is to elect some new younger hams to 
the ARRL Board to kick thai stodgy old or- 
ganization in the rear to gei it moving, And 
that's entirely up to your club, which is prob- 
ably also run by a bunch of old-timers, mired 
in 1930s thinking. 

Your choice for amateur radio: grow or go. 

\ ui! Sets 

Have you seen any snot-nosed kids around 
who might be helped on their downward 
path in life by an injection of the hamilis 
virus? This is one virus that not even the 
bjoeleeirifier can cure, and it's simple to 
administer, even in fulJ sight of the parents. 

How about sucking the unsuspecting 
protonerd in with a very simple crystal radio 
that can be built in about an hour? The parts? 
Some Tinkertoy spools to support a loop an- 
tenna, wire for the antenna, a pair of head- 
phones from the kid's Walkman IM , a diode 
and a tuning capacitor mutlc out of alumi- 
num foil? 

Well, thafs about what led me into a life- 
time of hamming. An angel, or a devil, de- 
pending on your viewpoint of me, brought a 
box of old radio parts into the Dutch Re- 
formed Church I was attending when 1 was 
1 4. He gave them to my heM friend, Alfie, 
who had zero inieresl in such junk and 
dumped 'era on me. I found a circuit in 
Popular Mechanics that used some of the 
parts ui make a cigar box radio. Unfortu- 
nately, it worked and 1 was hooked. For life. 

You'll find 15 easy-to-build crystal radio 
projects in the new Crystal Set Projects book 
from The Xtal Set Society, Box 3026, St. 
Louis MO 63130. Some great stuff here for 
science fairs, or even lor science classes, The 
160-page book is $17.50, including s/h. Be 
an angel or devil and get busy poisoning 
some dirty little minds with this book. 

Oh Oh Ozoned 

A reader sent me more data on the ozone 

ConLtmuxl on page 30 



Number 27 on your Feedback card 



Antennas for Amateur Television, 

Parti 

An overview of the most useful. 



E- 



NizarA. Mullani K0NM 

719 Santa Maria 

Sugar Land TX 77478 

il: [K0NM@amsat.org] 



Antennas play a major role in the 
transmission and reception of 
P5 pictures in amateur TV. Un- 
like commercial broadcasters, which 
transmit with millions of watts of effec- 
tive power from thousands of feet up, 
amateur TV is usually limited to a few 
hundred watts of effective radiated 
power from a couple of hundred feet 
of height. Therefore, the signal levels in 
ATV are much lower than for commer- 
cial TV, and high-gain antennas are 
necessary to provide high gain in both 
the transmission and the reception of the 
signal. And, in the fringe areas of recep- 
tion, a high-gain antenna can improve 
the signal strength sufficiently to over- 
come the noise so that a picture is 
visible. 

Several designs of antennas are used 
for ATV, which operates from 420MHz 
and higher. As the frequency of opera- 
tion is increased, antenna sizes become 
small enough to consider designs that 
would be prohibitively big for VHF op- 
eration. Some of these designs, which 
we'll touch on in this article, have fea- 
tures that make them very attractive 
for ATV, such as ease of construction 
and use. 

This first article in a two-part series 
will cover a few of the more common 
designs, while next time we'll discuss 
the esoteric antennas. 



The yagi 

Most amateur radio operators are fa- 
miliar with the yagi antenna, which is 
one of the most efficient antennas for 
producing high gain with the smallest 
amount of space and material. Its opera- 
tion is based on the principle of mutually 
coupled radiators that are resonant at the 
frequency of use, and which combine 
with the fed radialor to produce a unidi- 
rectional radiation of energy from the 
antenna. In other words, a dipole radia- 
tor, when placed adjacent to another 
dipole, will couple energy into the adja- 
cent dipole and the two dipoles will then 



radiate a pattern as if they were two 
phased dipoles. The two radiators tire 
then said to be mutually coupled be- 
cause they can interact mutually with 
each other By changing the length of the 
adjacent dipole and its spacing, the 
phase of the coupled energy is changed 
and the radiation pattern can be made 
unidirectional. 

As an example, if an element is made 
5% longer than the resonant frequency 
and spaced 0.2 wavelengths away, it will 
act as a reflector while an element made 
5% shorter and placed 0.1 wavelength 
away will act as a director. Adding more 
elements in the antenna concentrates 



1.5 A 



/=0.475A 0.46A 



0.44A 0.44A 0.43A 



0.40 A 



/ 



0.25A- 




0.31 A 



Reflector 



N 



300 ohm Line 



0.31 A 



0.01 A 



-^0.31A^* 



Metal Boom 



0.31 A" 



\ 



t 

0.01 A 



Driven 

Element 





Directors 



Fig. 1. Typical yagi antenna with one reflector, one radiator, and several directors. 

73 Amateur Radio Today * July 1 997 27 



more of the radiated energy into a narrow 
beam of radiation and increases the gain of 
the antenna. A typical design for VHF and 
UHF uses a radiator, one reflector and 
multiple directors as shown in Fig- 1. 

The yagi antenna does have its limita- 
tions, though. Antenna gains higher than 
12dB become harder to produce because 
of three major factors. 

The first is thai several directors are re- 
quired to increase the gain, which in turn 
increases the length of the boom sij 



cantly. As an example, to increase the gain 
by 2.5dB of a yagi antenna (from 12dB to 
14.5dB) requires a doubling of the boom 
length (from 2.2 to 4.4 wavelengths) and 
almost doubling the number of directors as 
shown in Fig. 2. 

The second is that longer boom lengths 
require more critical construction so as to 
reduce the losses caused by errors in spac- 
ing of the elements and the critical dimen- 
sions of the directors. At high frequencies, 
such as Ihe 1.2 and 2.4GHz bands, small 
errors in the size of the directors and re- 
flectors can have major influence on the 
gain. Therefore, high-gain UHF yagis be- 
come very long — and very difficult for the 
average ham to build. 

The third is that yagi antennas have 
a very narrow band of operation and of- 
ten have to be tuned to the specific 
frequency of operation. 

Other avenues 

There are several alternatives to the 
yagi antenna for use in the 400MHz and 
higher bands that have high gains, that 



are easy to build, and that do not have 
the limitations of the yagi antenna. In 
fact, 10 to 13dB of gain can be easily ob- 
tained with some designs requiring only 
simple materials found in the average 
hardware store. Some of these can be 
easily built and tested within a few 
hours — and work quite well for ATV. 

The cantenna 

The circular waveguide antenna is 
commonly known as the cantenna 
among ATV enthusiasts. Its theory 
of operation is based on the properties 
of waveguides. In proper-sized wave- 
guides, RF inserted into the waveguide 
will be propagated within the waveguide 
with very little loss. At the exit of the 
waveguide, the wave will exit at an 
angle that is inversely proportional to 
the length of the waveguide; the long- 
er the waveguide, the narrower the 
beamwidth of the radiation pattern. Di- 
mensions of the waveguide antenna are 
not critical, and feeding the antenna is 
very simple. Fig* 3 shows the design of a 
simple waveguide antenna that can be 
made out of household materials, such 
as coffee cans. The diameter of the cof- 
fee can needs to be between 0,7 and 0,8 
wavelengths in size, and the acceptable 
range in diameters and inches for the dif- 
ferent frequencies for ATV are shown in 
Table 1. 

The waveguide is excited with a quar- 
ter-wavelength stub inside the can 
placed a quarter- wavelength from the 
closed end of the antenna. The length of 




Fig. 2, Theoretical gain of the yagi as a function of number of elements and the boom length. 
28 73 Amateur Radio Today • July 1997 



Circular Waveguide Dish Feeds 


Frequency 
(MHz) 


Inside Diameter 

Circular Waveguide 

Range (inches) 


915 


8.52 - 9.84 


1296 


6.02 - 6.94 


2304 


3.39 - 3.91 


3400 


2.29 - 2.65 


5800 


1.34- 1.55 


10,250 


0.76 - 0.88 



Table I, Dimensions of circular waveguide 
a n i en na s for cliff e ren t A TVfreq itenci e s (from 
Ref L Table 5, p. 18-14), 

the antenna should be anywhere from 
two to five wavelengths, with the longer 
lengths producing greater gain. Beyond 
a certain length of the antenna, the gain 
will flatten out for the classic coffee can 
cantenna. 

The cantenna is probably one of the 
easiest antennas to build, and it will 
yield anywhere from 8 to lOdB of gain 
with very little effort. The simplicity o( 
the design, the construction, and the 
feeding of the radiator makes it a must 
antenna for all ATV enthusiasts. Famil- 
iarity with this design is important be- 
cause it is often used with higher-gain 
antennas, such as the parabolas, for 
feeding RF into the reflector. 

The helical antenna 

The helical antenna is a loop of wire 
that is helically wound with a circumfer- 
ence of approximately one wavelength 
and a reflector added to provide a unidi- 
rectional radiation pattern. This design is 
called the axial mode helix because il ra- 
diates most of its energy in ihe axial di- 
rection of the winding, compared to the 
normal mode which has a smaller diam- 
eter winding, and which radiates at a 
right angle to the winding, The normal 
mode helix is used in short antennas 
such as rubber ducky antennas. 

The axial mode helix has high gain 
and is a broadbanded design — a fasci- 
nating design because of its properties in 
creating circular polarized radiation. 
A typical helix has a bandwidth of 1.8 to 
1 so that an antenna designed for 
900MHz will easily work at L2GHz. 



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73 Amateur Radio Today • July 1997 29 




Fig. 3. Circular waveguide antenna (cantenna). The length of the 
antenna can be increased to 5 wavelengths for higher gain. The disc 
shown on the antenna is for use when feeding a parabolic reflector. 



UNBALANCED 
COAXIAL 

FtED 



REFLECTOR 



/ 



ow 



FEED 
WIRE 



Fig. 4* The helix antenna 



The mechanical layout of the design of a 
helical antenna is shown in Fig. 4. The 
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The advantages of the helical antenna 
arc that the construction of the design ai 








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30 73 Amateur Radio Today • Juiy 1997 



UHF frequencies is easy and non-criti- 
cal. This is not true ai the lower VHF 
frequencies, where it becomes diffi- 
cult to hold the helical windings in 
place. Another advantage is that the 
broadbanded nature of the device makes 
it easy to construct and use. The circular 
polarization of the antenna is useful 
where the polarization can fluctuate — 
as in satellite, balloon, or mobile trans- 
mission. The major disadvantage is the 
higher-than-normal feedpoint imped- 
ance, which requires a little bit of match- 
ing for 5012 operation. A winding of one 
wavelength in circumference, which is 
what is normally recommended for this 
antenna, will have a feedpoint imped- 
ance of approximately I40U and will 
change as a function of the frequency 
Therefore, the operation of this antenna 
into 50Q, will require some form of 
matching to the 140fi t such as a quarter 
wave of 9012 transmission tine. 

The yagi, cantenna, and helical are 
three antenna styles that are high in gain, 
easy to build, and a must for the ATV en- 
thusiast Next lime, well cover more 
ways to get the most gain from your 
ATV antenna system. 

References 

L The ARRL Antenna Rooh ARRL 
Publications, Newinglon CT, 1994, 

2. Antennas by John D. Krauss, 2nd 
Edition; McGraw-Hill International, 
New York NY, 1988. 

3. The Amateur Radio Handbook^ 3rd 
Edition; Radio Society of Great Britain, 
London, 196L 

4. Radio Handbook by William Orr, 
1 8th Edition; Editors and Engineers 
Ltd., Indiana, 1970. 



Never sby ate 

Continued from page 26 

layer peril and the terrible contribution to it 
by man's CFCs from Freon™ T hair spray, 
and so on. It turns out that most of the chlo- 
rine getting into ihe air comes from ocean 
spray, with a minor amount coming from 
volcanoes. Man's contribution, it turns out, 
amounts to 0.000015 percent. Which backs 
up my April editorial comment about 
DuPont™ paying off environmentalists to 
ban the use of Freon once their patent was 
running out, a shrewd political move which 
has cost us consumers (the suckers) hun- 
dreds of billions of dollars. Was thai you out 
there screaming for Congress to ban CFCs? 
And did you drive to school in a panic to 
grab that Alar^-sprayed apple from your 
child? 

If you keep re-electing your congressmen 
nothing is going to change. Give 'em all one 
term and out. Let's do away with those re- 
election campaigns and the bribery they fo- 
ment. We've tried using professional politi- 
cians and look at the mess we're in. so lei's 
start electing amateurs. Non-lawyers, if at all 
possible. 

Tandy™ Shakeup 

Thanks Rick KA5PVT, for the newspaper 
clipping about a major Tandy shareholder 
asking the board of directors to replace John 
Roach. Par's I'm concerned the Tandy board 
has to have been asleep for the last 15 years 
or they'd have canned Roach long ago. 15 
years ago Radio Shack™ had 40% of the 
personal computer market. Then along came 
IBM and RS sales plunged to around 4%. 

How'd IBM pull a coup like that? By do- 
ing exactly what I recommended Roach do 
with the TRS-80 computers. It was bad 
enough when J personally tried to convince 
Roach to open the TRS-80 operating system 
up. But when he refused to budge, 1 made the 
same recommendation in an editorial in 80- 
Micro, along with a prediction that if he 
didn't, the TRS-80 could get blown away. 

Since one of the key developers of the 
IBM PC system was a ham with whom Td 



gone on a DXpcdition to Navassa (KC4DX), 
I had more ihan an inkling of ihe IBM plan. 
As the editor and publisher of 80~Micro, 
which was running around 600 pages 
a month (the ihird largest magazine in 
the country), 1 had refused lo let Radio 
Shack advertise in my magazine devoted 
to the TRS-80 because 1 fell that Roach's 
marketing policies were too destructive. 

The Last Catlbook 

The 1997 North American edition has 
2*219 pages, is two and a half inches thick, 
weighs in at about Five pounds, and costs 
$40. Belter get one, since this is the end of 
the line — the last Call book they* re going to 
publish in book form. From now on it's only 
going to be on CD-ROM, which, as far as 
Vm concerned, is a royal pain in the ass. 1 
want a Caiibook in my office so I can look 
up ham addresses, I also frequently need it in 
the hamshack across the road. E can take it to 
where I need ii, whether ii*s to the typewriter 
for addressing an envelope, to my computer 
to put an address into my frequently used ad- 
dress file, or wherever. Even a five-pound 
book I can move to where I need it, A CD- 
ROM version is rooted to my computer and 
takes a lot longer to use- 
Similarly, I have a nice dictionary built 
into my Word program, but most of the time 
it*s faster lo grab the Funk & WagnaWs off 
the shelf. 

My ROM drive is usually kept loaded 
with my PhoneDisc so 1 can look up phone 
numbers and addresses. That's turned out to 
be very handy. So, unless you have a com- 
puter set up near your rig t you'd better grab a 
1997 Catlbook printed version while they 
last. 

Business Incubation 

A report in the April issue of Dividends, 
the Staples™ magazine for small businesses, 
shows that the success rate for new busi- 
nesses started in incubators is 80-90%, ac- 
cording to the Ohio-based Nalional Business 
Incubation Association, Compared to the 
normal success rate after five years of 
around 10%, this is a powerful recommenda- 
tion for business incubators. 

Several years ago I was approached by the 
School of Management at Rensselaer Poly- 
technic Institute to help them reorganize 
their curriculum. This resulted in my becom- 
ing a member of the RPI Council, the Steer- 
ing Committee, and their first Executive in 
Residence. Soon 1 was consulting for the 
president, which resulted in the founding of 
two entrepreneuriaJly-orienled new schools 
at the university. My consulting for their 
business incubator project resulted in their 
making some major changes, with their win- 
ning the prize last year as the best incubator 
in the country. 

What I'm proposing is a way for any small 
town or community to set up a small busi- 
ness incubator and start growing new busi- 
nesses. As our big businesses downsize and 

Continued on page 85 





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73 Amateur Radio Today • July 1997 31 



Number 32 on your Feedback card 



Home-brew Yagis 
For Amateur Television 



Easy to build, easy to use— and not just for beginners 



t 



Ed Manuel N5EM 

10430 Sage vate 

Houston TX 77089 



When the Houston Amateur 
Television Society (HATS) 
began to promote amateur 
television in our metropolian area, the 
Firsi order of business was to gel people 
watching the ATV repeater. It\ hard to 
get someone interested without seeing 
activity. Our repeater uses 421.25MHz 
i conveniently, cable television channel 
57), so just about everyone has an ATV 
receiver alreadv. All that is needed is an 
antenna. 

Almost everyone who has a televi- 
sion, also has an antenna. Unfortunately, 
421.25MHz is far enough from UHF 
channel 14 (480MHz) thai most com- 
mercial television antennas we have 
tried perform poorly unless the station is 
close to the repeater. Unless you live in a 
small area, you almost never get to point 
your antenna at the commercial TV sta- 
tions and at the ATV repeater at the same 
time. One amateur in Houston actually 
lives close enough to the repeater to 
watch ATV with rabbit cars— hut this is 
the exception. 






Photo A, The author, Ed Manuel N5EM. 
holds a 70cm ATVyagi and I JGH: vagi still 
under development. Activity hi the hack- 
ground is a North Texas Microwave Society 
antenna measuring party. 

32 73 Amateur Radio Today • July 1997 



For most of us, an antenna specially 
tuned for the ATV repeater is a better 
choice. 

A couple years ago I attended the Dal- 
las Hamfesl. A friend of mine (Kent 
Britain WA5VJB) was presenting an ar- 
ticle on his latest microwave develop- 
ment — a series of antennas for 2m 
through 23cm, for use with a rover sta- 
tion during microwave contests. Kent 
is aware of man\ other VHF/UHF pur- 
suits besides small signal contesting, 
and has created designs for amateur sat- 
ellite work, FM repealer work and ama- 
teur television* My attention was 
immediately captured. 

It soon became apparent that we had 
struck gold with Kent's design. In the 
two years since making the first antenna, 
we have distributed more than 100 of 
these as kits or finished antennas in the 
Houston area. They have proved to be 
easily reproducible and reliable. Many 
of them have been handed to new ama- 
teurs who have never built anything. 
Some hams were so new to amateur 
radio that they had only been active in 
two meters with hand-held radios. No 
one has ever tried to get one of these 
antennas working and failed. 

Many hams have been taught that 
yagis are nearly impossible to build 
properly. In every case, the problems 
can be traced lo the builder's failure to 
construct the antenna exactly as de- 
scribed. In order to make our antenna 
design reproducible, we decided to 
package them as kits, The kit solves 
many problems. By providing all the 
elements and a pre-drilled boom, along 
with a properly terminated coaxial 
pigtail, success is assured. 



Kent's antenna is a marvel of simplic- 
ity. He created a design thai keeps the el- 
ement lengths in even fractional-inch 
dimensions so one can measure them 
accurately with a simple ruler 

Materials include wooden booms and 
brass welding rod elements. The driven 
element is a J-shaped rod that resembles 
a J-pole antenna. By using a simple 
driven element and adjusting the spacing 
of the reflector and first director, Kent 
managed to make the feedpoinl impedance 
of the driven element match the desired 
feedline impedance without an adjust- 
able match. This removes the greatest 
challenge for the inexperienced huilder. A 
typical 421.25MHz receiving antenna is 
very difficult to adjust by normal methods. 
Most hams don't have a 42 1 .25MHz trans- 
mitter with a 75Q output and 7512 SWR 
bridge — but all one has to do is adhere to 
the design and the match is so close no 
adjustments are needed. 

Construction is simple 

Stan b\ buying good quality one-by- 
twos or one-by-threes (I prefer poplar 




Photo H* Close- up of the yogi feedpoint . The 
shield goes to the ha If- wave portion of the 
driven element, while the center conductor 
goes to the quarter-wave par torn. Note the 
thicker area of the boom . 



with oak as a second choice), and rip 
them into square booms, 3/4-inch x 3/4- 
inch by six feet long- If you don't have a 
table saw, just ask around on the local 
VHF-FM repeater. A short section of the 
boom is cut off and glued to the back of 
the boom (Fig, 1). This double- wide sec- 
tion does two things: It provides a larger 
area for mounting a U-boll and it pro- 
vides some additional boom width for 
the driven element- The J section is a bit 
wide for the 3/4-inch boom. After mea- 
suring the hole spacing along the boom 
and drilling the holes (1/8-inch for the 
welding rod), the boom is ready and can 
be put aside. 

It takes about 15 minutes to cut out the 
brass rod elements. (Sec Table 1 for 
dimensions and spacing information.) 
There is some waste since brass welding 
rod typically comes in 3 6- inch lengths. 
The best method is to cut the longest 
rods first (reflector end of the antenna). 
After each cut, measure the leftover 
piece and compare it with the shorter 
lengths required. If you need to make 
other antennas for higher bands (smaller 
elements), then you don't have waste, 
you have extra material. 

Clean up the ends of the elements with 
a file and insert them into the boom ac- 
cording to length. They go longest to 
shortest from rear to front. Center them 
with a ruler, When you like the place- 
ment of all elements, put the antenna 
into a vise and put a drop of glue or ce- 
ment on each element where it enters the 
boom. I like to use a thick cyano-acrylic 
glue (SuperGIue™) that is sold in model 
shops. It is available in a quick-drying 
formula that makes it easy to work with. 
You could also use epoxy cement. When 
the glue or epoxy is set, turn the beam 
over and do the other side. Leave the 
antenna overnight until the glue is 
completely dry, 

Now attach the feedline. This is a 75ft 
antenna, designed to feed the 75S2 input 
of your television. The pigtail is a short 
length of RG-59, RG 6 or other 75Q 
cable. Solder this cable to the feedpoim. 



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Look for cable with a copper or tinned 
(solderable) braid. It's not possible to at- 
tach the aluminum foil-shielded types of 
cable to the driven element. One type of 
cable I prefer is a 75Q Teflon™ type 
used in air plenums in office buildings. 
This cable has a Teflon outer jacket and 
inner dielectric. The braid is made from 
copper wire and the center conductor 
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dering to the 1/8-inch brass welding rod, 
One local antenna builder buys regular 
RG-59 cable at Radio Shack®. Careful 
soldering avoids the need for Teflon, but 
it's not easy. Pre- tinning the brass rod 
at the points of attachment makes this 
process easier. 

Terminate the pigtails in a standard 
"F" connector (crimp type). This makes 
it ready to connect to an **F* type bar- 
rel for connection to your feedline or 
allows easy insertion of a TV type 
preamp if needed. If you want to build 
your preamp, the ATVers in Atlan- 
ta published a neat design (see Bill 
Brown WBSELK's "ATV" column, 73, 
September 1994). 

The builder must give careful thought 
to weatherproofing these antennas. The 



K 



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Fig. 1. Specs for a driven element. 



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boom is wood and will absorb water, 
ultimately warping. Some builders use 
two or three coats of quality outdoor var- 
nish, followed by two coats of an out- 
door lead-tree enamel (stealth gray, of 
course). The feedpoint should be giv- 
en several coats of clear paint 
(Rust Oleum™) to keep the solder 
from weathering. The connectors are 
not weatherproof and must be pro- 
tected as any other connector. Use some 
good product like Coax-Seal™ or RTV™ 
(non-corrosive electronic type). 

As with other UHF antennas, the 
higher this antenna is mounted, the 
better — with one caution: There is no 
need to gel the antenna higher than ab- 
solutely necessary. If you get perfect 
reception at 35 feet but have a 90-foot 
tower, resist the urge to go to the top. 
Thai additional feed line to set to the 

■■-■ 

top has loss. It is quite possible to lose 
signal by having more fccdline loss 
than you would have if you mounted it 
just high enough to clear local clutter 
and vegetation. Since this antenna is 
designed to be rear- mounted, it is per- 
fect for mounting on a tower leg and 
pointing (permanently) at the ATV re- 
peater. Remember that this antenna is 
designed for 421.25MHz. That's a re- 
peater output frequency and is rarely 
used for point-to-point operation. If 
you want to chase DX to distant re- 
peaters you might want to mount the 
antenna on a rotatable mast. If you 
find you need a very long feedline, 
you should consider using RG-1I in- 
stead of the smaller, more lossy cables. 
You might also find you can get 75S2 
hard line used to build cable television 
systems from your local cable TV com- 
pany for free. Any length less than several 
hundred feet is scrap to a cable company. 
Connectors are a bit difficult to obtain, bul 
are not that difficult to make. 

If Lhis antenna is not big enough for 
your location, there are other options. 
You could get a commercial antenna, 
like the M2 440-21 ATV. This antenna is 
over 14 feet long and is one of the larg- 
est commercial ATV antennas available, 
An alternative to purchasing a commer- 
cial antenna is to phase an array of two 
or four of these home-brew yagis. Two 
will provide almost 3dB of additional 
gain. Four will provide almost 6dB more 
gain. The stacking distance is a modest 
28 inches and an array of four is not 
impractical. 
34 73 Amateur Radio Today * July 1997 



Phasing multiple antennas 

For 70cm ? remember that we are deal- 
ing with 75 Q antennas, In Houston we 
have chosen to parallel two antennas 
with an F-type tee. The resultant imped- 
ance is now 37.5£1 At this point, a quar- 
ter-wave transformer of 5012 cable 
brings the impedance up to 75 £2 again. If 
you want to phase four together, you 
simply do this twice. The recommended 
stacking distance is 28 inches, which 
makes a nice, compact array. If you 
make your 75fi pigtail from the antenna 
20 inches long (approximately 19 inches 
after you strip and attach it to the driven 
element), you will have a perfect length 
to reach the tee. You can find RG-58 
cable with a solid center conductor 
which can be terminated in F connec- 
tors. We currently have a couple of dual 
antenna arrays in Houston (and plans to 
build a quad array). 

One last note about stacking is: When 
viewed from either the front or rear, your 
driven elements should appear identical. 
The J driven element wc are using has a 
long side, a short side and a folded end. 
Each part of the element should be posi- 
tioned exactly as every other element. If 
you inadvertently flip one, you will have 
it out of phase with the rest of the array. 
Double-check to make sure that you are 
feeding the end of the short side and 
have attached the shield of the coax to 
the center of the long side. These little 
things can really mess up the pattern and 
performance, and are hard to fix after 
putting the array in its final mounting 
position. 

Your antennas should match the polar- 
ization of your ATV repeater. In Hous- 
ton, we use horizontal polarization on 
70cm and vertical on all other bands. Of 
course, that is always subject to local de- 
cision and changing RF environments. 

There are certainly other antennas that 
can be used for ATV. The yagi described 
here is just one approach. We have found 
it to be easy to build and very effec- 
tive — great for the new ATVer. 

Additional documentation on the an- 
tennas is readily available to those who 
wish to make one for other bands. You 
can make a call from a FAX machine to 
our fax-back server in Houston, Just call 
(713) HOT-FMTV and follow the in- 
structions to get the antenna documents, 
which include designs for every band 
from two meters to 23cm. 



I strongly encourage ATV clubs to 
consider making kits like this available 
to hams in their communities. If you 
want to promote ATV, it's easier to hand 
someone a kit and show him how to 
make it work, than it is to tell him how 
and expect him to do it. Wc have sold 
these kits in the Houston area for $15. 
You could build them for about $10 but 
you would have to gather all the pieces. 
Many people would like to have ATV re- 
ceive capability but will never get 
around to it. Put a kit in their hands. Get 
them receiving the local activity and 
they will get interested in a hurry — al 
least, they will if your ATV activity js 
interesting — but that's another article, 



70cm Yagi for 421.25 MHz 

(75n Feedpoint Impedance) 


Element 


Length 


Location 


Reflector 


14.00 


0.00 


Driven 
Element 


13.00 


3.00 


Director 1 


12.50 


6.50 


Director 2 


12.25 


12.25 


Director 3 


12.25 


17.75 


Director 4 


12.00 


24.50 


Director 5 


12.00 


30.50 


Director 6 


1 2.00 


36.00 


Director 7 


11.75 


43.00 


Director 8 


11.75 


50.25 


Director 9 


11.50 


57.25 


Note: If rear 
space must I 
reflector. 
All dimensioi 


mounting i 
De left behi 

is are in in 


s desired, 
nd the 

ches. 



Table J. Dimensions and spacing for the 
elements. 



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Number 35 on your Feedback card 



Rocket Video 



Video beyond the speed of sound. 



Jeff Johnson KC5AWJ 

17423 Landon Oaks Drive 

Houston TX 77095 

[kc5aw|@ stevens.com] 



Have you ever been inside a 
sonic boom? Most people 
haven't, except for the few 

people Hying military jets or the 
Concorde. With ATV, you can do it, 
without leaving your lawn chair 

Pushing the edge 

We have a group within the Hous- 
ton Amateur Television Society, Inc. 
(HATS), that is constantly looking for 
new and interesting ways to use ATV. 
We are the "toy" group: those who are 
looking for strange and exotic video 
viewpoints. I've been Hying model 
rockets since the late '60s but had grown 
away from it during college, About four 
years ago a long-time friend invited me 
to one of the South Texas Balloon 
Launch Team meetings and introduced 
me to HATS, Several members were 
getting into the next level of rocketry — 
amateur rockets. They had oulgrown the 
smaller Esles rockets and were reaching 
for the stars — or parts of the upper atmo- 
sphere, I went to a couple of the rocket 
launches, scheduled events requiring 
FAA flight clearances, and met some- 
one I recognized It was my family phy- 
sic i an , a licensed manufacturer of 
Acrotech™ reloadable rockel engines 
under the "Dn Rockel, Inc." name, He 
was fascinated by amateur television, 
and was interested in using it in rockets 
to record the flight and aid in recovery. 

Early attempts at ATV were cumber- 
some, and not too impressive. A guy fly- 
ing his 8mm camcorder had much belter 
video,., until the flight when the para- 
chute didn't open and the camera re- 
corded six inches into the ground. Wilh 
newer equipment and smaller cameras 
now available, a more robust ATV sys- 



tem can be flown. It still costs as much 
as a good camcorder but allows instan- 
taneous viewing, doesn't suffer from the 
tape being pulled away from the record- 
ing heads by G force, and allows the re- 
cording of a flight where a tape system 
would destroy itself and the tape. 

This system is being designed for a 
rocket with an outside diameter of 
98mm. about 3.9 inches. To balance the 
engine system, the rocket and electronics 
must weigh almost 15 pounds. The en- 
gine system is a reloadable "N" moron 

If you launched rockets as a kid, you 
probably used B4-2. C6-5 and D12-7. 
This alphanumeric naming has some 
forethought to it. For every increase in 
letter designation, the power of the en- 
gine doubles. Two * 4 Bs M equal one "C\ 
two "Cs" equal one 4t D"... which makes 
an "N" motor roughly equivalent to 2Ms 
= 4Ls = 8Ks = 16Js = 321s m 64Hs = 
128Gs = 256Fs = 512Es = l024Ds = 
2048Cs. This is not something you bu\ 
at the local hobby shop! One of the re- 
quirements for purchasing motors of this 
class is membership in a recognized 
amateur rocketry organization and 
successful flight demonstrations to 
flight observers certified in the motor 
classifications of intended use, 

A reloadable motor has a hisher initial 
cost than a single-use engine but also has 
the advantage of being reusable — simi- 
lar to the space shuttle's solid fuel boost- 
ers without the O-rings. Our rocket is 
projected to fly to 30,000 feet at a speed 
of more than Maeh 1.6 (about 1,100 
miles per hour). 

The plan 

We wanted to create a system where 
as much information as possible about 



the flight was sent to the ground fast 
enough to provide time to react in prob- 
lems (the nose didn't separate: the main 
parachute didn't deploy), so we could 
send a ground command to correct the 
errant system. To accomplish this, we 
have two microcontrollers, with sensors 
for G-force, velocity, temperature, and 
absolute pressure, in conjunction with 
two video cameras providing a view 




Photo A. Mockttp of nose cone with rumeras 

ami transmitters approximately positioned. 

73 Amateur Radio Today • July 1997 35 



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36 73 Amateur Radio Today • July 1997 




Photo B. 

one audio 



Delia prototype transmitter with 
channel installed. 



straight out from the rocket (the horizon 
camera), and another looking down and 
along the rocket (the "been there** cam- 
era). The horizon camera will display 
sensor information using a two-line 
video title chip fed by one of the control- 
lers. Both cameras feed separate trans- 
mitters (one with audio to hear the 
BOOM) and then combine at the high 
power amplifier to be transmitted 
through one J-pole antenna. 

The body tube diameter (inside diam- 
eter of 3.625 inches) was a compelling 
reason to repackage the Houston Ama- 
teur Television Society (HATS) TR1 
"Charlie" revision transmitter into a I 
form that could be reshaped based on 
available space. The Delta transmitter 
can be separated into three separate 
modules and positioned as needed to fit 
small spaces. The Delta modules be- 
came small enough to allow the entire 
video system inside the nose cone, It 
also helps to have a nose cone almost 4 
inches in diameter and 20 inches long! 
Most model rockets aren't this big! 

We had to create a small mixer board 
that would combine the two video sig- 
nals and adjust the power level before 
feeding it into the high power amplifier 
(HPA). Several ideas were proposed, but 
the easiest solution won out. We had two 
50-ohm signals that we wanted to 




Photo C. The view from approximately 3,000 
feet. On a very good day with three stages, 
an Estes Farside™ could get to tittle more 
than half this height. (Photos pom South 
Texas Balloon Launch Team's flights J 



combine into one 50-ohm output and at 
the same time cut the power level. A 
small piece of copperclad, three chip re- 
sistors picked by using a neat little pro- 
gram created by Teledyne, and we have 
a pad to adjust the power level into 
the high power amplifier, lust what the 
doctor ordered! 

The cameras 

The horizon camera used is a color 
teleconferencing camera made by 
Intel™. It is a standard output NTSC 
(RS-170A) unit with resolution of 330- 
350 lines and amazing light sensitivity 
(near \ lux). The camera lost 348 grams 
with the removal of the swivel base and 
steel RF shield, to weigh in at 72 grams. 
One really nice feature of this camera is 
the power switch. In the original case, 
opening or closing the lens cover would 
turn the camera on or off. I can wire the 
camera so it runs any time power is ap- 
plied or add a relay to one of the control- 
ler boards and control the camera with 
the microprocessor unit. 

The "been there" camera is a high- 
resolution color board camera from 
Edmund Scientific™. It has NTSC out- 
put, 450 lines of resolution, 5 lux sensi- 
tivity, and a 3.8mm f/5 lens. It weighs 68 
grams. It is rated for only 6.8G non-op- 
erational, so additional work will need 
to be done to keep this camera in one 
piece and operating at I0-15Q. 

The video transmitters 

Two Delta transmitter prototypes are 
being used: one is video only at 
1247MHz, and the other has one audio 
channel at 1255MHz. The VCO sections 
have been separated and stacked under- 
neath the audio/video section. 

Antenna 

The first pass antenna is a J-pole 
driven element from the HATS 20-eie- 
ment yagi for 1 2GHz, A null is expected 
to appear as the rocket gains altitude. We 
will compensate for this by having the 
receivers positioned about one mile 
from the launch site. Depending on how 
much this null interferes with reception, 
we may need to use a quarter-wave stub 
under a ground plane to reflect the signal 
down toward the ground. The stub-un- 
der-ground has worked well for South 
Texas Balloon flights but does require 




Photo D« The halfway point for a normal 
flight, 18.000 feet. 

lhat the antenna remain in a more or less 
vertical orientation. 

Controller board 

The controller has yet to be finalized 
(at this writing). The microcontroller 
(MPU) is a Microchip PIC 14000 which 
contains 7 A/D channels with 10-16 bit 
resolution, an internal temperature sen- 
sor, internal watchdog timer, and up 
to 20 I/O pins for digital controls. Pres- 
sure sensors consist of a Motorola 
MPX5100A absolute pressure sensor 
and a Motorola MPX5500DP differen- 
tial pressure sensor The absolute pres- 
sure sensors will be used to calculate 
approximate altitude while the differen- 
tial sensors will provide velocity data. A 
Motorola MMAS40G10D accelerom- 
eter chip (0-40G) will provide accelera- 
tion rate information. The MPU will use 
its internal time of flight counter, alti- 
tude data, velocity and acceleration to 
determine where it is in the projected 
flight path. This information will deter- 
mine when the rocket will separate at 
apogee (maximum height) and when the 
main chute will deploy at approximately 
2,000 feet above the launch site. This in- 
formation will also be displayed on the 
horizon video channel using an NEC 
uPD6450 video titler chip. 




Photo E. The Gulf of Mexico is visible from 
30,000 feet, the projected range of the 
author $ project rocket. 



Nose cone 

The nose cone itself is 19.375 inches 
long, 3.875 inches in diameter An addi- 
tional 12 inches of length will be added 
to the nose cone for ballast and batteries. 
It is being constructed using E-Glass™, 
an aerospace application Fiberglas™ 
reinforcement, and five-ounce Kevlar* 
in the structural reinforcement areas. 
Lexan® ^windows" will be molded into 
the glass reinforcement. 




Photo R Only rockets on steroids get up to 
93 ,000 feet. Barely visible midway across the 

photo is probably Venus or Mars. 



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73 Review 



Number 38 on your Feedback card 



Full Rock and Roll 



The AT- II Automatic Antenna Tuner from LDG Electronics. 



Marshall G. Emm AA0XI/VK5FN 
2460 S. Moline Way 
Aurora CO 80014 

E-mail: [aaOxi@mtechnofogie3.c0m] 



For several reasons, I have always 
been skeptical of automatic tuners. 
First, for the most part they are very lim- 
ited in the degree of mismatch that they 
will handle Second, they most I \ "go 
with" an expensive transceiver they 
have been specifically designed for. 
Third, and most important, they have 
been extremely expensive, especially for 
something that is usual!) a ham's first 
home-brew project- — made nut of old 
radio pans and junk. 

The AT-1 1 is relatively inexpensive, it 
works well and it will work with any 
transceiver — just hook it up in your 
shack in place of your existing manual 
tuner connect 12V, and you can almost 
forget it's there. The AT- 1 1 was origi- 
nally published about 18 months ago as 
a QST project, and is now available in 
two separate versions — a QRP version, 
and the QRO version (which 1 built for 
this review). Either version can be pur- 
chased with or without a nicely laid out 
enclosure. The QRP version is small 
enough to fit inside some QRP trans- 
ceivers; the optional enclosure for the 
QRO version is only 6,5 x 8,5 x 2,5 
inches. That makes it very attractive for 
mobile use. 



How it works 

The AT^ 1 1 uses 17 relays to switch be- 
tween combinations of eight fixed in- 
ductances and eight fixed capacitances 
in either a low- or high- impedance con- 
figuration (the capacitance is switched 
to either precede or follow the induc- 
tance in a traditional L configuration). 
Thus fherc are 256 inductance combina- 
tions possible, and 256 capacitance combi- 
nations possible in either high- or 
low -impedance configuration, for a grand 
total of over a quarter million tuning com- 
binations. The AT- 1 1 uses its microproces- 
sor to set combinations of inductance and 
capacitance, and check the SWR with each 
one, until a suitable match is found. De- 
pending on how many combinations are 
tried, the unit will require from one-tenth 
of a second to 6.2 seconds to either find 
the match or indicate that one can't be 
found. The current SWR reading is indi- 
cated by three LEDs: green, 1 -5: 1 or bet- 
ter; yellow, 2: 1 or better: and red, greater 
than 3: 1 . The intermediate ranges of 1 .5- 
2 and 2.5-3 arc indicated by lighting two 
adjacent LEDs. So, for example, if both 
the yellow and red LEDs are lit, you will 
know that the SWR is between 2.5: 1 and 




INO 



3«mi 



O * 
*~<» 



SWR / Statu* 



* 




• » « 

1.5 2.0 >a.O Tuning 



AT- 11 Automatic Tun&r 




Photo A. Hie AT- H Automatic Tuner is 
38 73 Amateur Radio Today * July 1997 



to go. 



3:1. A fourth LED indicates thai tuning 
is in progress. After tuning, the AT 11 
"goes to sleep" so that stray hash from 
the processor doesn't interfere with 
reception. 

The AT- 1 1 has two modes of opera- 
lion — automatic or semi-automatic. In 
fully automatic mode, the tuner "wakes 
up" when you transmit monitors the 
SWR, and immediate!) attempts a re- 
match if the SWR increases to more than 
3:1. In semi-automatic mode, you can 
push a button to make the AT-1 1 go into 
the tuning algorithm at any time. In ci- 
ther automatic or semi-automatic 
mode, you can use four buttons on the 
front panel to increase or decrease either 
inductance or capacitance by one step at 
a time. This last feature is particularly 
useful because in seeking a match the 
AT-1 1 will stop if it finds one with a re- 
sulting SWR of 1.5:1 or better Thus, the 
tuner may stop with a L5:I match in 
situations where a closer match can be 
attained; you may be able to get it closer 
to 1 .0: 1 by nudging the buttons. I know, 
the textbooks say that for all practical 
purposes you might as well leave it at 
1 .5 to 1. With QRP gear, however the heal 
generated by an SWR of 1.5:1 in the final 
transistor can be harmful — and it is often 
fatal (to your final, that is) to operate these 
rigs with an SWR of 2 to 1 ! 

Another aspect of the tuner that I 
should mention is power handling. The 
QRO version of the tuner is speed at 
100W but will in fact handle about 
150W on a 50 r /r duty cycle (e.g., CW 
and SSB>. When tuning, of course, there 
can be combinations which result in 
high voltages on the relay contacts and 
stray RF around the eireuil board, so 



LDO recommends tuning with 10W or 
less — the AT-ll will respond with as 
little as 2 W of applied RF. 

Construction 

In some respects the AT-ll is very 
easy to build but it can be frustrating be- 
cause of discrepancies between the silk- 
screen overlay on the board, the overlay 
diagram, the pans list, and the sche- 
matic. Most such problems should be 
rectified by the time this review sees 
print, so keep in mind that the comments 
were based on the version current when 
I built it. 

An experienced builder will require 
five or six hours to complete the kit — 
there are over 200 components and 500 
solder joints, so do take your time! 

The kit will require a high level of 
soldering skill — many of the tracks are 
quite close and the components are 
small. For example, the 1/8W resistors 
are about half the size of those most of 
us are used to working with, and the pro- 
cessor chip socket has 52 connections. 
An added complexity is the addition of 
five components on the foil side of the 
processor socket — these are extremely 
close solder pads and in one case you 
need to tack the leads from three compo- 
nents to a single pad. 

There is a reasonably complex bifilar 
transformer, and eight toroidal inductors 
to wind. The instructions tire clear, and 
only the transformer is really challenge 
ing, The eight toroids are quite large, as 
is the wire, so you should have no diffi- 
culty if you follow the instructions. An 
easy mistake, though, is to wind in the 
wrong direction, in which case the re- 
sulting coils will not fit properly on the 
board and you will have to do them over. 
The transformer is a little more difficult, 
but certainly not beyond average skills. 
Note that it is mounted flat to the board, 
though, or you will have difficulty run- 
ning the antenna input wire through the 
middle of it! 

Apart from the winding of toroids, the 
instructions are somewhat rudimentary, 
and you will be well advised to read 
through the entire manual before touch- 
ing the board with a soldering iron. 

First, as is my normal practice, I sol- 
dered in the IC socket, and I suggest that 
any builder should start with that. The 
first soldering instruction in the manual 
is: "Parts are installed and soldered in 



order of height, from shortest to tallest. 
With the PC board blank, it is easiest to 
install all of the resistors first/' The 
problem with that is that a number of the 
resistors share a solder pad with another 
component (e.g., 18 or more transistors) 
and if you aren't extremely careful you 
will occasionally fill the other hole with 
solder. Ifs fairly easy to identify those 
situations as you go and postpone the re- 
sistor until you do the other component, 
but the point is that you don't always 
have to follow the instructions step-by- 
step, and in this case it might be a good 
idea to exercise a little discretion. Tick- 
ing the components off on the overlay 
diagram as you install them is a good 
way to keep track. 

There was a problem mounting the 
ribbon cable connector on the board — it 
may be rectified by the time you read 
this, but the pins are too big for the 
holes. The solder pads are not large 
enough to drill the holes out, so LDG's 
recommended solution is to tack-solder 
the connector to the board and then ffow 
solder through the holes from the other 
side. The result is quite strong enough, 
and electrically sound if you have in fact 
determined that solder has flowed 
through onto the pins, The one large di- 
ode is also too big for its britches, but I 
found that those holes could be drilled 
out enough to make it fit. If you don't 
have a small enough drill, you can of 
course solder the diode to the top of the 
board. 

Two of the .01 caps turned out to he 
"ring-ins." I had three left over when I 
thought I was finished, so I did a com- 
parison between the schematic, the parts 
list, and the parts overlay. The parts list 
accounted for 53; add two (which don't 
have C numbers) for the processor mod 
and that makes 55, or one left over. 1 
checked them off one by one and discov- 
ered that not only had I not installed C67 
and C7Q, I couldn't figure out where 
they were supposed to go, According to 
the schematic they should be located 
near the power switch, but everything in 
that part of the board was accounted for 
Eventually I had to contact LDG for 
clarification, and was informed thai (a) 
there was an extra cap supplied, and (b) 
C67 and 70 had been deleted from the 
power input and ^relocated" near relays 
8 and 17. Sure enough, they do appear 
on the parts overlay diagram and there 
are holes on the board for them, Pd 



missed them because with that one ex- 
ception the parts lineup for each relay is 
identical. By the way, LDG's support, 
in the person of Dwayne Kincaid 
WDSOYG himself, w r as fast and courte- 
ous. Help Wilt be available if and when 
you need it. 

The smoke test 

Once the board is complete, you arc 
instructed to connect power and check a 
couple of voltages and current before in- 
serting the CPU chip. The only trap here 
is that if you have been following the 
instructions exactly, you will have 
mounted the power jack on the circuit 
board, but you haven't yet connected the 
switch — to apply voltage to the circuit 
you need to either hook up the power 
switch or apply the supply voltage to 
the hot side of the switch pads on the 
board. 

The next step is to install the board 
in the (optional) enclosure, wire up 
offboard connections, and insert the 
CPU chip (using standard anti-static pre- 
cautions, of course). The panel wiring is 
straightforward, as long as you are very 
careful with the ribbon cable, I made a 
mistake and cut one lead to the wrong 
length, so I had to repair it, When Fd 
finished the wiring, it seemed sensible to 
create another testing stage and repeat 
the power-on checks before inserting the 
CPU chip, and the clacking of a relay 
told me that I had indeed been wise. One 
of the tacked-on components on the bot- 
tom of the hoard had been pressed 
against another pin on the CPU socket. 

Calibration has a catch to it, loo. It 
should be very easy, since all you are do- 
ing is setting the pickup voltage level for 
the SWR circuit and balancing the for- 
ward and reverse detection circuits, but 
the instructions have R53 and R54 re- 
versed- Fortunately, common sense says 
that when you are measuring the for- 
ward voltage you adjust the trimpot la- 
beled "fwd," not "rev." And experience 
says that if you use the R numbers in the 
manual you will not align your tuner, pe- 
riod. Once the unit is aligned and you 
are ready to test it, you are in for some- 
thing of a shock. Push the tune button 
and you will think you are about to be 
bitten by a rattlesnake— it sounds as if 
all the relays are spazzing out, but it 
turns out that what you are hearing is 
perfectly normal. You get used to it 
73 Amateur Radio Today * July 1997 39 




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quickly and then you will be impressed 
with what the unit is actually doing. 

The AT-11 in operation 

This is a nice device to use; it's fast, 
precise, and reliable. There are finite 
limits to the degree of mismatch that it 
will tune, but in practice I suspect that an 
antenna that can't be matched with the 
AT- 1 1 isn't going to be much use as an 
antenna anyhow. Sure t with the right 
combination of added inductance and 
capacitance you can "match" a piece of 
concrete — that doesn't make it a good 
antenna! In any case, it's probably fair to 
say that the AT- 1 1 is more versatile than 
it looks. There is only a single SO-239 
coax jack for the antenna output, but that 
does not mean it will only tune antennas 
fed with 50S2 coax, If you open up a 
tuner that has outputs for balanced trans- 
mission line and single wire, what do 
you find? The single wire connection is 
just connected to the coax jack, and the 
balanced line terminals are connected to 
a balun. It's very easy to turn a PL-259 
coax plug into a connector for a single 
wire, and you can always add an exter- 
nal balun either at the back of the tuner, 
at one of the outputs of a following coax 
switch, or even outside your shack. 

The AA0XI antenna farm consists 
of a weedy crop of miscellaneous 
skyhooks, including an R7 vertical, 
resonant dipoles for 30 and 40 meters, 
and a shortened all-band doublet fed 
with 450Q ladder line. The AT-1 1 tuned 



everything perfectly, insofar as it found 
a better than 1 .5:1 match on all the bands 
I use, with the antennas I normally use 
for those bands. It also gave me a good 
match for the R7 on 80m and matched 
the two dipoles and the vertical on six 
meters! 

One minor drawback in shack opera- 
tion is that the AT-11 will not preserve 
settings with the power off. That's just a 
fact of life when you use relays, which 
after all made the project a lot more fea- 
sible, and affordable, than one using mo- 
tor-driven roller inductors and vacuum 
variables. And the AT-1 1 does take some 
power to run. Momentarily during tun- 
ing it is possible for all of the relays to 
be energized at once, resulting in a cur- 
rent drain of half an amp. A more typical 
load is 200mA average. 

The AT* 11 was not the easiest kit I 
have ever built, but over time I believe it 
will prove to be exceptional value for 
money — especially if it performs as well 
in a mobile or portable environment as it 
does in the shack. 

The LDG AT-11 Automatic Antenna 
Tuner kit is supplied in several different 
combinations of board kit, enclosure, 
QRP/QRO version, factory assembled... 
too many variations to list here, so con- 
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what*s available and current pricing. 
LDG Electronics, 1445 Parran Road, St. 
Leonard MD 20685. Phone, (410) 586- 
2177; FAX, (410) 586-8475; E-mail, 
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40 73 Amateur Radio Today • July 1997 



Number 41 on your Feedback card 



Tiny Power 

A big little switcher for ATV (or other} uses 



Ron L. Sparks KC50DM 

24818 Lakebriar Drive 

KatyTX 77494-1809 



I never could pass up a challenge. 
While m\ brother and I live in the 
same state, we are still 400 miles 
apart. During a recent visit a hit of remi- 
niscing was in order As children we en- 
joyed building model rockets. This led 
lo him saying, "Since passing 40, I am 
now allowed some * middle age crazy/ 
The kids and I have gone back to build- 
ing rockets. Why don't you use your 
ham radio stuff to build us a payload?" I 
told him that I thought I could build an 
amateur TV (ATV) payload if he could 
give me eight ounces of net weight. 

The challenge 

This weight would give him a real 
challenge. Neither of us like the idea of a 
multiple-engine craft because it is diffi- 
cult to guarantee simultaneous ignition 
of the engines. If only one lights you can 
easily create a "land shark." This is not a 
pretty thought, especially with a couple 
of hundred dollars worth of ATV gear in 
the nose! 

Fig, 1 shows the block diagram for the 
ATV system. As it turned oul the trans- 
milter and camera portions were easy lo 
build. Commercial kits are now r small 
enough to handle these tasks and are rea- 
sonably priced. The most ungl amorous 
part became the challenge. To power the 
CCD camera and a one- watt transmitter 
about six to seven watts of power supply 
capability with at least a dual voltage 
output would be needed. All this had to 
work from the lightest most inexpensive 
batteries available, which led to the 
following design specifications: 






Input 


4.5 volts minimum, 12.6 
volts maximum 


Output 


13,8 volts regulated at 
300 - 400 mA, plus 9 
volts regulated at about 
100mA 


Ripple 


as low as possible. 
preferably below 1% 


Battery 


0.5 to 1 Ah (amp-hour) 
with a maximum weight 

of 3 02, 


Power 
supply 
weight 


less than 1 oz, 



A close review of the Enercef* Battery 
Guidebook showed that while lithium bat- 
teries have the highest energy density (i.e., 

most Ah for the least weight) their cost 
would be prohibitive, at about $11 each. 
The i wo remaining choices with high 
enough maximum current output were al- 
kaline and NiCd. The problem with either 
of ihese was getting enough cells stacked 
for a manageable voltage boost with- 
Oiit falling out of the range that an inex- 
pensive regulator could handle. As you 
will see later the power supply performs 
flawlessly, but battery weight is still a 
challenge for the rocket system. 

Circuit description 

Old-style linear power supply de- 
sign was as solid and smooth as a diesei 
engine, and almost as heavy — our new 



project called for a supercharged high- 
rpm aluminum race engine. The 
switching power supply fits this analogy 
very well Several years ago they were as 
complicated lo design and use as a race en- 
gine. However, technology has advanced 
rapidly and National Semiconductor™ 
makes a line of integrated circuits called 
Simple Switchers'. I looked carefully over 
their product line with a supplier catalog 
close at hand, and found the LM2577-ADJ 
series fit my requirements nicely. The part 
was small, readily available, and reason- 
ably priced in single quantities from Digi- 
Key™. 

The design process begins with the 
data sheet. The data slice l circuit proved 
lo be effective in its simplest form, Fig, 
2. my project's circuit, uses this form 
with a secondary voltage regulator. The 
figure also shows component values 
needed to meet my requirements. The 
equations to calculate the specific values 
are not complicated, but they are a bit te- 
dious. National provides design soft- 
ware from their Web site at the URL 
(Universal Resource Locator) [hup:// 
www.nationalxom/design/index.html], 
vJiich will save you the drudgery. The 
program is MS-DOS based, but is solid 
and robust. Alternately, the equations 
from the data sheet could be placed into 
a spreadsheet with the same results. It is 
very helpful to use one of these com- 
puter-assisted methods since several 
cycles through the calculations are 
needed to find the optimal balance be- 
tween weight (e.g., will a heat sink 
be required?), component size, input 
voltage range, and ripple. 

73 Amateur Radio Today • July 1997 41 



ANTENNA 



CAMERA 



COMPOSITE VIDEO 



MICROPHONE 

& 

MIXER 

— z^ — 



AUDIO 



\ 



TRANSMITTER 



w 



AUDIO ID'ER 



POWER SUPPLY 

(FEEDS ALL SECTIONS! 

7^ 



BATTERY 



Fig, /, Creating an ATV transmitter relies on the power supply. 



The operation of the circuit is straight- 
forward. An internal NPN switching 
transistor pulls the junction of the indue- 
tor and diode to ground, allowing energy 
to be stored in the inductor. When a 
maximum current is sensed, the transis- 
tor cuts off, allowing the energy to be 
discharged and stored in the output ca- 
pacitor. A divider on this output voltage 
provides the control to adjust the current 
maximum required to keep the output 
regulated. 

There are some unusual consider- 
ations in the components to be consid- 
ered. First, Lhe current through the 
inductor is not a steady state value. This 
means that lhe instantaneous maximum 
inductor current and LM2577 current 
can be about five times the load current. 
When selecting the coil, this maximum 
current must be considered to avoid 
saturation of the coil core and poor regu- 
lation. Also, the switching transients are 
large. This means that the output capaci- 
tor must have a low internal series resis- 
tance to handle the high frequency part 



of the filtering job. 
The program pro- 
vided by National 
calls this the E.S.R. 
Unfortunately, 
most of the manu- 
facturer's specifi- 
cations for capaci- 
tors defined this in 
terms of dissipation 
factor — tan 5. The 
conversion equa- 
tion is E.S.R, = tan 
5/coC, where co 
takes on its tradi- 
tional value of 2 x re 
x f (C is in farads, 
f is in hertz and 

E.S.R. is in ohms). 
In my system this meant that RS.R. = 

tan 5/(27tfC) = tan 8/349. Just be sure to 

select a capacitor with a tan S that is as 

low as possible. 

Construction 

There are no critical concerns for 
component layout or construction 
methodology. During the design of the 
supply you will need to determine 
whether a heat sink is necessary for the 
IC, but other than that, any construc- 
tion approach should be acceptable. In 
the case of the supply shown in Fig, 2 S 
calculations show no heat sink is re- 
quired, up to a total current of about 
425mA and ambient temperatures 
below 110°F f but the unit will operate 
very hot. The junction is rated for 
operation at 257°F (]25°C) and the 
program designs lor Ihis. Case tem- 
peratures can easily boil water or burn 
fingers, so use a heat sink if you have 
room for one. 

The circuit was first constructed and 
tested using the multicontact solderless 



LI 
100 uH 1N5817 



Bl , 
6.2 V 



B2 
6.2 V 



CI 

33 uf; 

16 V 



C2 
0,470 UF 




LM 2577-Adj 




m Vout 
O 13.8 V 
<320mA 



LM7809 



C3 

1000 uF 

40V 



O 9.0 V 
<100 mA 



<? 



vg 



Fig, 2. Putting it all together into a workable circuit. 
42 73 Amateur Radio Today • July 1997 




Photo A, Prototype desi\ 

solder less breadboards . 



is easy on 




Photo B. Mission accomplished— seven watts 
of regulated power the size of a quarter! 



breadboard system shown in Photo A. 
Once operational specifications were 
confirmed, the circuit was reconstructed 
on a Surfboard™ to keep its size and 
weight to a minimum. The end result is 
shown in Photo B. 

How the circuit was moved to the 
Surfboard deserves a few comments. 
Each point of connection on the sche- 
matic was labeled with a node letter and 
then a table was constructed with each 
node and the components connected to 
it. Using this table allowed the circuit to 
be redrawn into a configuration that fit 
the Surfboard with a minimum number 
of jumpers; the result is a very compact 
package, weighing only 1/3 ounce (9.5 
grams). The quarter in the photo 
weighed 1/4 ounce (7 grams). 

Testing 

Your testing will probably only re- 
quire basic voltage checks on the output. 
Just be sure to put a power load resistor 
on the output so that the supply is at 
least minimally loaded during testing. I 
wanted to perform a more thorough test 
for this project, however — with two ob- 
jectives; First, it was important to verify 
that the supply was operating properly 
and was stable throughout its input 
operating range. Second, an estimate of 
battery life was needed. 

Fortunately, DMMs have now become 



15 
H 



5" 

o * 



i - 



7 - 



i - 



5 -h 



4 - 



t - 



REGULATION CAPABILITY 




7 



SUFFICIENT DRTVE 
NSUFBCENT 6ATTBW 



T 



7 



1! 



9 



VOLTAGE IN 



Fig. 3. A good battery is essential, but this little supply can deal with nearly anything. 



so inexpensive (under $20 each) that I 
had enough to monitor inpui voltage, 
output voltage, and output current simul- 
taneously. Fig. 3 shows a plot of input 



C1 



C2 



C3 



Parts Ust 

33nF, 16V electrolytic 

470nF f ceramic 

1 .OOOiiF, 40V 
electrolytic with low 
E.SiRi 

IOOjjlH, 2.5Apeak 
current inductor 

20.51(12, 1% surface 
mount 

2-Okn, 1% surface 
mount 

3.0W2, 5% surface 
mount or 1/8W 

1N5817 or equivalent 
Schottky Diode (1 .OA, 
Vmax = 20V) 

LM2577T-ADJ 

National 
Semiconductor 
switching regulator 



Optional, but recommended: 

Heat sink 23°C/W or better 
for Ul 

Surfboard™ circuit board 



L1 



R1 



R2 



R3 



D1 



U1 



voltage versus output This was per- 
formed with a 100mA load on the 9V 
output and a 325mA load on the 13.8V 
output (a total of 425mA on the sup- 
ply). Input was from two Duracell* 
size "J" alkaline photo batteries wired 
in series. You can tell from the curve 
that things took an unexpected turn at 
this point. When loaded with a 10% 
load (35m A) t everything operated per- 
fectly. However, with the full load ap- 
plied, the input current demand was so 
high that the batteries could not meet 
the demand, This led to an interesting 
investigation of batteries (see Side- 
bar). When larger batteries were used, 
the system worked as desired. 

The curves show that the circuit was 
regulating well within design require- 
ments down to a battery voltage of 



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73 Amateur Radio Today • July 1997 43 



4.2V and then degraded "gracefully/ 1 
An oscilloscope was placed on the out- 
put throughout the test and showed no 
peculiar changes or transients through- 
out the testing. There was, however, a 
high frequency switching spike on the 
output. Depending on your require- 
ments, further filtering or shielding 
might be necessary. 

Fig, 4 shows the regulator case tem- 
perature versus time, From this you 
can see that the power dissipation 
through the switcher is greatest toward 
the end of battery life when the boost 
requirement is the greatest. This may 
make a difference depending on your 
application. 



Results 

As you can see from the testing, all of 
the specifications were met successfully. 
The total final weight was 033 ounces 
(9.5 grams). The output voltage stayed at 
a stable 13.8V down to an input voltage 
of 4.3V (when given sufficient input cur- 
rent). The best result of all is that I not 
only have a useful power source for my 
MicroAXV system, but I am no longer 
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A Battery Tale 

During the testing of the power sup- 
ply, I was forced to learn (or is it re- 
leam?) a few lessons about batteries* 
The first thing to remember in any 
boost-operating regulator is the old 
adage of "no free lunch " The power 
in must be greater than the power out. 
For example, that means that even if 
the regulator is nearly 100% efficient; 
the input current at 6 volts has to be 
greater than 1 amp to provide the 
rated output (13.8 volts @ 425mA). 

The Enercef* Battery Guidebook is 
an excellent source of information on 
small batteries. This book showed the 
size "J" batteries to be rated at 0.55Ah 
(amp-hours). I knew that batteries are 
rated for a 10-hour discharge rate, but 
I expected their performance to be 
reasonably linear. The most common 
model for battery calculations is a 
pure voltage source in series with a re- 
sistor. That resistor is called the inter- 
nal resistance of the battery. If a 
battery were perfectly linear, that re- 
sistance would be the same for any 
discharge rate. Using such a model 
implies thai the "J* battery could put 
out about 1.1 amps for 30 minutes 
(LI A x Q,5h = 0.55 Ah). What I dis- 
covered was that for discharge rates 
less than the nominal 10 hours, the 
nonlinear behavior was severe. The 
life of the "J** batteries at those 
extreme loads was measured in sec- 
onds, not minutes! Based on this 
result, the battery size had to be in* 
creased to a lOAh camcorder battery 
to test the supply at full load. This is 
too heavy for the rocket, so we are 
still searching for alternatives. 

I think it would be an interesting 
project to run a series of discharge 
tests and calculate the change in inter- 
nal resistance for various battery 
types. This would determine just how 
much we could push certain types of 
batteries. I suspect that similar charac- 
teristics will exist in each family type 
(nickel-cadmium, alkaline, lithium, 
etc.). If any of you have done tests 
like this, I would be interested in 
knowing the results. Better yet, find a 
student and help him/her make this 
into a science fair project — we would 
all benefit from that. 



Number 45 on your Feedback card 



Finding His Voice 



Two young women found an urgent need for CW skills. 



Jennifer Sanders 

with Jacqueline Sanders KB6MTV 

320 Camino Al Barranco 

LaSelva Beach CA 95076 



In 1983, when my sister and 1 were 
young girls (I was around 13 and 
my sister Jacqueline was about 
eight), my father Jack, began to teach 
the l wo of us Morse code. He had just 
earned his General class amateur radio li- 
cense (KB6MLO) and he fell lhat it was 
never too early to start leaching his chil- 
dren. At the time, the two of us had no idea 
how important learning Morse code would 
prove to he later on in our lives. 

We come from a family of hams. Both 
of my father's parents earned their ama- 
teur radio licenses in 1956 while living 
in the Panama Canal Zone. My dad's fa- 
ther, Bruce G. Sanders, Jr., started out 
with the callsign KZ5SS, and his mother 
Dorothy's call was KZ5SN. At the lime, 
the KZ call was used only for Panama 
Canal Zone residents. After they retired 
and moved to Arkansas, their callsign s 
changed to WA5NUP and WA5NUQ. 

My father did not earn his license until 
years later, around 1982, He started out 
with the call KB6MLO and quickly 
raced through to getting his Extra class 
license and a new call, WX6X. He be- 
came very involved in amateur radio and 
eventually hecame the president of his 
local amateur radio club in Santa Cruz, 
California, in 1988. He was very active 
and interested in getting the community, 
especially the younger generation, in- 
volved in amateur radio. He felt that 
amateur radio plays an important part 
in the community. He and my sister 
Jacqueline both operated the emergency 
ham radio frequency for Red Cross 
emergency communications during the 
days immediately following the Loma 
Prieta earthquake in the San Francisco 
Bay area in 1989. 



During my faiher's most active ama- 
teur radio years I was a teenager, and 
though J learned the basics of the code, 1 
never completed my training and did not 
earn a radio license. At that age I felt that 
there were other, more important, things 
to pursue, whereas my sister at age eight 
picked up the code and the theory 
quickly and began studying for her Tech- 
nician license (this was before there was 
a "No-code" Technician). 

Way hack then, 1 fell, as many people 
do today, that Morse code was an archaic 
thing to be learning. I am a child of the 
computer age and learning something so 
primitive seemed ridiculous. What was I 
ever going to use Morse code for in an 
age where FAX machines and cellular 
telephones are so common? Luckily for 
my sister and me. our father did not 



think lhat the code was so outdated. He 
stressed thai the code still had its place, 
and 1 learned the basic dits and dahs of 
the code alphabet* My sister became 
very proficient with Morse code, studied 
hard, and went on to earn her Advanced 
license at age 10 (KB6MTV) while my 
father earned his Extra. 

Our father had moved to Florida to 
continue his education and was working 
on a Ph.D. in Computer Technology in 
Education, He still had been using ham 
radio, although much less frequently, 
and he still knew Morse code. In late 
1996, he was to put his Morse code 
knowledge to good use. 

On Sunday, December 15, 1996, Dad 
was riding his motorcycle home in 
Sarasota after completing his Sunday af- 
ternoon ride with a few of his friends, 




Photo A. Jack Sanders WX6X using a practice key to send code to his daughter Jacqueline 
KB6MTV. 

73 Amateur Radio Today • July 1997 45 



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when a car pulled out of a driveway 25 
feet in front of him. As always, rny fa- 
ther was driving carefully and wearing 
the usual protective gear: a Bell ap- 
proved helmet, leather jacket, and 
leather boots. He slammed on his brakes, 
but he did not have enough time lo avoid 
the car. His head hit the bottom fender of 
the driver's side of the car as his motor- 
cycle slid on its side. 

He suffered massive fractures to his 
face, especially the right side, and broke 
three vertebrae in his neck. He was air- 
lifted by helicopter from the accident 
scene to Bayfront Medical Center, about 
40 miles away in St. Petersburg, where 
he was admitted in critical but stable 
condition, and was placed on a life sup- 
porting respirator. 

He underwent a 10-hour brain and fa- 
cial surgery on December 19, 1996. He 
had facial reconstructive surgery, his jaw 
was wired and he was given a trache- 
otomy. His right eye was so damaged 
from the impact of the accident that it 
could not be saved and unfortunately 
had to be removed. Thankfully he suf- 
fered only minor brain injury and came 
through the surgery well. 

This began a nine-day stay in the in- 
tensive care unit while he recovered 
from his surgery. He appeared to be 
doing well, and the doctors told my sis- 
ter and me that he was progressing nor- 
mally. The problem was that although 
my father was coherent and conscious, 
he could not communicate because his 
jaw was wired shut, and the respirator 
that pumped air to his lungs through 
a hole in his throat made it impossible 
for his vocal cords to work. He could 
not see out of his left eye because his 
face had been so severely injured that 
the eye was still swollen and his vision 
was extremely blurry. The injury to his 
neck had made his upper body, espe- 
cially his hands, incredibly weak; it 
was impossible for him to hold a pen or 
pencil. 



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My sister and I began to think about 
how we could communicate with our fa- 
ther. He was essentially in the dark and 
unable to communicate with us or his 
doctors and nurses. He could squeeze 
our hands to reply "yes" or "no" to any 
of our questions, but he was unable to 
tell us anything. 

Then we remembered Morse code. 
My sister is not an active ham and had 
not used the code in quite a while. I had 
not used it in about 13 years, but we de- 
cided that if our father could send it 
to us, then we would force ourselves to 
remember. 

We bought a practice key at a local 
amateur radio shop and brought it to the 
hospital. My sister put the key under- 
neath my father's right hand, placing his 
index finger on the key pad and asked, 
"Dad, do you think that you can send us 
Morse code on this key?" He sent back 
".. -.-. .- -.". Once I heard his "voice*' 
through Morse code, 1 knew he was 
going to be okay. 

Within a few days, my father was strong 
enough to send code steadily, It was an in- 
credible relief for him to be able to com- 
municate and it was wonderful to know 
what he was thinking. In no time he was 
sending pages and pages of code. 

He was moved to a regular room for 
further recuperation. He still was using 
the key to communicate wilh us, but 
since none of the nurses or doctors 
could understand Morse code, my sister 
and I took turns staying with him around 
the clock to translate and assist him. He 
always had the Morse code key by his 
side, night and day. Hospital personnel 
would hear the noise from the key as 
they were walking down the hall and 
come into the room to find out what 
was going on. We received many enthu- 
siastic comments on what a brilliant, 
helpful method of communication the 
code was. We were definitely the talk of 
the nursing staff. 

My father was moved to Health South 
rehabilitation hospital in Sarasota FL on 
January 13, 1997, and is now able to speak 
again. Since that time he has often men- 
tioned that Morse code really saved him. 
He says that before he was able to com- 
municate he was frustrated, scared, and 
alone in the dark in his hospital bed. 
Whenever he mentions those times I think 
about how very scared I was until we 
tried using the code — and how much of 
a difference it made in all our lives. 



46 73 Amateur Radio Today • July 1997 



Number 47 OH your Feedback card 



Bicycles Across Switzerland 



QRPing through beautiful Switzerland by bicycle is a blast 



f 



Stephen Stuntz NOBF 

RO. Box 1462 

Loveland CO 80539 



I arrived in Zurich un August 30, 
1 996, with a home-brew 30-meter 
CW transceiver (designed by 
NN1G), a 2-meter Standard C108C 
handheld, and an HP-200Ix palmtop 
computer (to send CW). Both radios^ 
and the palmtop, were powered with AA 
batteries. The 30 meter dipole. made 
with thin wire and RG-174 coax, was 
stored on a cardboard toilet paper roll by 
lucking the coax inside and wrapping 
the wire ouiside- The Swiss PTT govern- 
ment agency had mailed the temporary 
license. HB9/N0BR to Loveland 2 
months earlier thanks to the assistance 
of the ARRL, 

We took a bus south ti> Einsiedeln, a 
picturesque winter vacation village with 
cobblestone streets leading through the 
town center to an old abbey. We spent 
the morning adjusting to the 8-hour jet 
lag: shopping, resting, and touring the 




Photo A. Author operating at hotel in 
Bomngen. (All photos courtesy of author.) 



16th-century abbey, with its paintings, 
stained glass windows and a beautiful 
black stone Madonna, Alter a delightful 
lunch, several of our group headed to die 
hotel, overlooking the abbey, for a nap. 

In the afternoon I spent half an hour 
setting up a 30- meter anlenna from my 
second-story balcony, by uncoiling each 
leg of the dipole off of the cardboard 
tube. The tube was taped to the balcony 
railing and each leg was attached to trees 
below, in an inverted vee configuration. 
Each leg was installed by tying one end 
of a length of fishing line to the anlenna 
and the other end to a small lock. After 
tossing the lock off the balcony, I went 
outside, found the lock, pulled the dipole 
leg taut and lied the fishing line to a tree 
limb or fence post. The RG-174 coax 
was pulled out of the cardboard tube, un- 
coiled, and routed through the balcony 
doortotheNNlG. 

After connecting the headphones and 
the palmtop CW keyboard, I tuned 
around looking for some hams, but only 
heard one loud commercial RTTY signal 
on 10.110 MHz. Sending a CQ on the 
palmtop didn't result in a response, so I 
turned on the C108C and scanned 2 
meters with no luck. Feeling disap- 
pointed, I headed downstairs to pick up 
my bike and prepare it for the next day's 
trip to Rappcrswil. 

The next morning Herman, our Dutch 
bicycle leaden yelled out "*on your 
biiiiiikes!" as he hopped onto his bike 
from a running side leap, to lead our 
group over the breathlaking foothills to 
Ziirichsee (see means lake in Switzer- 
land). On descending hills overlook- 
ing Zurichsee, 1 pulled the C108C out of 
my pannier and scanned 2 meters. The 




Photo /?. Ham gear on Frihourg hotel desk. 

miniature handheld stopped scanning in 

a lull quieting QSO spoken in German. 
Jim N0GTW, who had stopped to inter- 
pret, heard the two voices say "have a 
good day" before they signed off. We 
couldn*t key the repeater, so we hopped 
buck on our bikes* to catch the rest of 
our group, who had disappeared down 
the trail. 

That afternoon, after we returned to 
Einsiedeln, I packed Ihc 30-metcr station 
into a backpack and headed up a steep 
grassy hill in back of ihe abbey. The trail 
meandered through pastures where 
sheep and cattle grazed, making beauti- 
ful music as the bells on their necks 
rang. After a steep ascent I slopped 
where the trail passed by a lall statue of a 
monk. The geometry was perfect — and 
irresistible. 1 strung together a sloper 
antenna by draping one leg from ihe arm 
of the statue and attaching the other le« 
to a picnic bench below. A group of 
singing nuns walked up, sat on the 
bench, and began a prayer meeting 
around the statue that 1 was using as an 
antenna support! 

73 Amateur Radio Today * July 1997 47 



Embarrassed, I sheepishly repacked 
the antenna anil headed up the trail for a 
second try, to another picnic area under a 
tree, The 30-meter band was in the same 
lousy condition as on the previous night 
excepl for a loud commercial RTTY sta- 
tion. It started to pour just as a faint CW 
signal front England appeared on 10,120 
MH/. so I scurried back to the hotel. 



U A group of singing nuns 

began a prayer meeting 

around my antenna-support 

statue!" 



The next evening we arrived in 
Beckenried for a one-night stay. Still op 
tiniistic, I set up an inverted vec and 
scanned 30 meters. The band was alive 
with signals coming in from all over Eu- 
rope, but I was unable to strike up a 
QSO. I also scanned 2 meters but didn't 
hear a souk 

We pedaled to Bonigen. nestled at the 
foot of the Eigen Jungfmu and Monk 
mountains near lnterlaken. On Septem- 
ber 3, in this picturesque valley on the 
crystal-clear Brienzer See, where the el- 
evation changes from under 1000 feet to 
over 13,000 feet in a few miles, I final Iv 
worked several stations. 



Ras HB9ACV gave me a full quieting 
report from Burgundy, France, on 2 
meters, from the shore of Brienzer See. 
Ras told me that he had moved from 
Switzerland to France 5 years ago but 
had not changed his calUign because of 
the retesting involved. The repeater that 
Ras and I used must have been placed 
high in the Alps to provide such excel- 
lent results with only 200 milliwatts! 
Later. I answered HB90 in Lucerne to 
ask about the location of the repealer 
and he asked, 'Sprechen sie DeutschT* I 
had to answer, "No!" 

Back ai the hotel I was feeling dis- 
couraged about my inability to commu- 
nicate on 30 meters and didn't feel 
motivated to set up a neat antenna in- 
stalled with fishing line away from the 
building. Instead I tossed the hot dipole 
leg out the second story, over a tree limb, 
and dangled the shielded leg out the 
window against the hotel to the ground. 
This configuration looked more like 

■»■■■ 

a tilted teepee rather than an inverted 
vee. At 9:30 PM, Olc OZ5DL, in 
Copenhagen answered a CQ keyed from 
the palmtop on 10.105 MHz. in spite of 
the unusual antenna configuration. He 
gave me a 569 signal report, said *73," 
and began chasing DX. Next I received a 
549 report from Gunar YL2PG, of Riga, 
Latvia, on 10.110 MHz. Gunar was 
transmitting 100 watts into a dipole- 1 
felt more confident after completing the 



QSOs because it seemed obvious that 
previous difficulty communicating on 
30 meters was due to poor propagation 
and not operator error 

After leaving Bonigcn. our group ped- 
aled south to Bern, the capital of Swit- 
zerland. On the main street, between the 
river and the old city gate (built in 
1200), stood Albert Einstein's house, 
where he lived and worked as a patent 
clerk, as he developed the Special 
Theory of Relativity. I paused there, 
feeling a sense of awe. thinking of how 
he had increased the understanding of 
physics, including radio waves used by 
ham operators all over the world. 

From Bern we pedaled further south 
to Fribourg. On September 7. I put the 
C108C in the backpack and went shop- 
ping in the town square. At 5 PM, on lop 
of a hill, 1 scanned 2 meters and found a 
repeater on 145.65A05 MHz. busy with 
QSOs spoken in both French and Ger- 
man. Heinz HB9AGB, in Bern, re- 
sponded to my call and explained that 
the repeater was located in the Alps 
North between Bern and Fribourg. He 
also explained that German is spoken by 
people living north of the repeater and 
French is spoken by the people living 
south. 

At 8:10 PM, Jan SP2EXE. from 
Wejherowo, Poland, gave me a 569 sig- 
nal report on 10.112 MHz, using Ihe 
same teepee antenna configuration that 




Photo t\ The bicycle tour group in front of a picturesque chalet. 

48 73 Amateur Radio Today • July 1 997 



had worked in B6nigen. Al 9:30 PM I 
answered Roy GW3SYL, in Bridgend, 
England, on 10,105 MHz t as he was 
signing off. He gave me a 579 reporl and 
stayed on the air for a few minutes be- 
cause he wanted Id hear about the QRP 
setup. 1 was surprised at the strength of 
my signal report because the NN1G 
power output was falling below half a 
watt due to low battery voltage. With no 
plan to recharge the batteries, I decided 
to pack the 30 meter rig away for the 
remainder of the trip. 

On the final leg of the trip we pedaled 
through the Gruyfere Valley to Montreux 
on the northern shore of Lake Geneva, 
the area known as the "Riviera" of Swit- 
zerland. I was not able to contact any 
hams in Montreux because the C108C 
receiver was overloaded due to cell 
phone transmitters. 

On September 11 at 5:00 AM, our 
group boarded the bus to the Zurich air- 
port, and by 7:00 PM we were back in 
Denver. As soon as I arrived home in 
Loveland I got on 2 meters and notified 
my friends in the Colorado QRP Club of 
the contacts I'd made in Switzerland. 
They reported thai the HF conditions 
had been lousy and they were surprised 
that 1 had made any contacts at all. I 
shared my pleasure in communicating 
successfully with a simple antenna 
tossed out the window. They reminded 
me that the ability to communicate on 
HF is affected more by the condition of 
the ionosphere than it is by the quality of 
the antenna. 

Next, I sent an E-mail message to 
dinar, and 10 minutes later he re- 
sponded from Latvia! He explained that 
he worked for the FCC -equivalent gov- 
ernment agency in Latvia. A few days 
later I received a picture QSL postcard 
from Riga. 

I am planning to bring ham radio 
along on the next Colorado Mountain 
Club bike trip to Italy. Some of the 
preparations include: 

1. Applying for a reciprocal license, 
(Hopefully, ARRL/FCC will be success* 
ful in achieving reciprocal licensing, 
eliminating the need for a temporary 
license.) 

2. Considering 40 or 80 meters until 
the solar cycle picks up, 

3. Taking along a bicycle mobile whip 
antenna, 

4. Learning to speak some Italian; 
getting on SSB instead of CW. 







Photo ZX Author s favorite bike trail, in the Alps looking toward the Gruyere Valley. 



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73 Amateur Radio Today • July 1997 49 



aw 



Number 50 on your Feedback card 



Ham Television 



Bill Brown WB8ELK 
139 Angela Dr. Apt. B 
Madison AL 35738 
E-mail: [bbrown@ htwaay.net] 



Last February 22nd, members 
of the HALO I High Altitude Lift 
Off) group gathered at the old air- 
port in HunLsvillc Alabama, to 
launch their latest balloon experi- 
ment. This was a test of the up- 
link and command module lor a 
future roekoon (rocket launched 
from a balloon) flight. 

The experiment 

The payload, designed by Ed 
Myszka KE4ROC consisted of a 
live color TV camera (from North 
Country Radio) that pointed down 
at the Earth below and also at a 
series of experiments that could 
be seen in the camera's Held of 
view. Four experiments were vis- 
ible: a red LED connected to one 



of the command channels. two 
rope cutter mechanisms and a 
small model rocket. The idea was 
to activate each of the experi- 
ments via a 2m touchtone uplink 
command and a custom touchtone 
controller board that Ed designed 
using a CM8880 DTMF decoder 
IC by California Microelectron- 
ics* The ATV transmitter was a PC 
Electronics KPA5-F and the an- 
tenna was an Olde Antenna Labs 
Mini- Wheel . 

In addition to the \J\ >\>iem. 
Ed included an APRS- form acted 
packet downlink on an Alinco DJ- 
180 tuned to 145J9MHz using a 
PacCOMM Pico-Packet Com- 
panion GPS board and a MIM 
packet module. The MIM board 
[available from Clement Engi- 
neering, (410) 268-67361 actually 
takes in the serial data from the 
GPS board and converts it directly 
to packet data. 





Photo B. CIose*up view of the balloon payload. Note the generous 
use ttf the scientist s secret weapon— duct tape. 



Photo A. Ai Wright (left) and Tim Pickens of the HALO group 
prepare the ATV balloon pay load for flight . 

50 73 Amateur Radio Today * July 1 997 



In a separate package , I made 
up a very small 10m CW beacon 
on 28.322MHz (20 milliwatts) 
that would transmit for at least 
two weeks, 

Ups arid downs 

Gene Marcus W3PM and Ed 
KE4ROC set up their ground sta- 
tion on picnic tables underneath 
a sheltei Inflating LhebaUOOll wm 
a bit tricky due to high winds, but 
we were finally able to string ev- 
erything together and prepare for 
liftoff, 

Even with the high winds, we 
had a picture-perfect liftoff as the 
balloon headed off to the strato- 
sphere, Ed had a microphone on 
the side of the package hooked up 
lo the ATV subcarrier and it was 
quite fun to hear our cheers of 
excitement downlinked from the 
balloon. It was neat to listen to the 
microphone audio. Cars and dirt 
bike noises could be heard by the 
balloon package from several 
thousands of feet of altitude. 
On one occasion we could hear a 
distant jet engine as well. 

The jet stream was quite strong 
that day and the balloon quickly 
drifted toward the cast and Chatta- 
nooga, Tennessee. At times the bal- 
loon was traveling over 150 mph. 



At 80.000 feet, we decided to 
lire offthe experiments. We could 
clearly see the red LED turn on 
and off when we hit the proper 
touchtone sequence. One of the 
rope cutters fired off as well. Un- 
fortunately, ihe other cutter and 
the model rocket did not fire off. 

The balloon popped at 90,000 
feet over the eastern part of Chat- 
tanooga and parachuted down to 
land in a heavily forested wilder- 
ness area near Lake Qcoee, very 
neanhe site ol the Olympic kayak 
races. The APRS GPS data 
worked well, but many partici- 
pants had difficulties receiving 
the signals. It turned out that the 
radio had its 5kHz offset turned 
on, which made it difficult to re- 
ceive. Nevertheless, we had good 
position data down to the last 
7,000 feel. This helped to narrow 
down the search area to within a 
mile, but a mile in the u ildemess 
is not quite the same thing as a 
mile in a cow pasture, let me tell 
you! 

The search 

Trying to play catch-up with a 
balloon traveling 150 miles per 
hour was a challenge, but the 
chase cnew that left the launch site 
(Robby Sperr KF4LFQ. Patrick 



Bramlctt KE4QIC, JaredCassidy 
KQ4VT and Chris Richardson 
N^QVI) closed in on the payload 

with help from Bill Nolle 
WAS1NZ, who relayed coordi- 
nates to the team via HF and 
APRS. They were in a remote 
mountainous region and finally 
gave up the search after trumping 
through the woods for several 
hours in the dark. They were re- 
ceiving weak signals from the 
payload, but could not pinpoint its 
location. Over the course of the 
next week, Rex Wagner, a rela- 
tive of one of our team members, 
was able to see what he thought 
was an orange parachute dangling 
from a treeiop on a ridge about 
two miles from the overlook 
where he was standing, but was 
unable to figure out just how to 
get to it. 

Willi this information in hand, 
I headed out to the area the next 
w r eekend with Greg Allison, 
Chuck Grarioli, Ralph Fowler 
N4NEQ and Eddie Foust 
WD4JEM Ralph and Eddie had 
an impressive array of DF equip- 
ment at their fingertips and spent 
the afternoon taking readings 
from many locations surrounding 
the payload. 

At first 1 tried to find a road that 
would get us close to the payload, 
but when I saw the house at the 
end of the road — with trash scat- 
tered everywhere, pit bid Is roam- 
ing free and the stuffed dummy 
(at least 1 hope it was a stuffed 
dummy} hanging from the tree 
limb — 1 decided that hiking in 
through the woods was a better 
choice! 

We hiked in as far as we could 
while tracking the very weak 
(about 0.2 milliwatts) 2m har- 
monic from the 10m beacon. Greg 
hacked his way through the ter- 
rible web of brambles with a ma- 
chete. It was incredibly slow 
going and we were ail slashed up 
by the thorns at the end of the day. 
Just at sunset we finally got a very 
strong reading and realized that 
we were probably only a few hun- 
dred feet away. It was difficult to 
turn back at this point, but we 
didn't want to get stuck in the wil- 
derness in the dark. 

We met up with Ralph and 
Eddie and narrowed down our 
search area with their DF data. It 
appeared that we were only 400 



feet away when we had to turn 
back. Ralph had an interesting en- 
counter with one of the local store 
owners during their search, lie 
had this tale to relate about their 
search: 

Late in the afternoon, Eddie and 
Ralph piled out of Eddie's Trooper 
at a small grocery store and began 
using the hand-held VFIF beam to 
take additional bearings on the 
package. This was to be our best 
bearing from the southeast side of 
the landing site. The lady working 
in the store wanted to know what 
we were up to... 

"Looking for the Energi/er' 
Bunny?" 

"Yes, ma'am." Ralph replied. 
Then he told her what they were 
rcalh doing. 

She said (clueless as ever), 
"Well — I have lots of Energizers 
in here, but I think they're all 
turned off." Ralph and Eddie 
shook their heads and said the 
only thing they could in this 
situation: 

""Well, ma'am, as long as he's out 
there, we'll be out here looking/* 

The recovery 

As we headed back home that 
evening we talked to two of the 
local hams on the repeater, Joel 
Gamble K04QC and John 
McClary KD4AFW. Even though 
John was 15 miles west of the 
landing site, he tuned in to the 
10m frequency and had an S-9 
signal from it! They were so ex- 
cited about the prospect of find- 
ing a balloon package that Joel 
headed out with his friend Rusty 
Doling AE4BK over the next two 
days. As Rusty provided him with 
DF bearings, Joel finally found 
the package just a few hundred 
feet south of the point where we'd 
given up the search. It was 90 feet 
up in the tree and the mode] rocket 
was lying on the ground below it* 
Meanwhile, Tim Pickens and 
Gene Young K4ZQM* of our 
HALO group, had headed into the 
woods with a long pole and a 
three-wheeler motorbike. They 
encountered Joel and Rusty as 
they were on their way out With 
their directions to the tree and by 
DFing the transmitter with an HT, 
Tim and Gene were finally able 
to reach the site and rescue the 
payload after it had been in the 
woods for nearly 10 days. 




Photo C* Clay Sawyer (left) and Ed Myszka KE4ROC inspect the 
reco vered pay toad. 



When Tim and Gene stopped 
back at the grocery store at the 
traiihead, the owner told them, "I 
didn't want to scare you fellers 
during your search in the woods, 
but look at some of the critters we 
hunt back there."' What followed 



was page after page of photos 
showing 400-pound black bears 
and sharp-tusked wild boars. We 
decided it would not be a good 
idea to land in the wilderness any- 
more unless we could take Daniel 
Boone with us. 




Photo D. Close-up view of the TV camera lens and plastic cover 
assembly. 

73 Amateur Radio Today • July 1997 51 



Homing in 



Number 52 on your Feedback card 




JO© Moeil RE. K0OV 

R O. Box 2508 

Fulterton CA 92837 

E-mail: [Horningin@aoLcom] 

Web: [http://members.aol.com/ 

homingini] 

Follow the f luxgate 

**Has the bearing shifted?" 1 
wonder how many hundreds of 
limes I have asked thai question 
of my navigator when I've been 
driving on a mobile hidden trans- 
mitter hunl (T-hunt). A sudden 
change of bearing means that you 
are getting close and it's time to 
pay more attention to cross streets 
and side roads. A few seconds of 
inattention at this point could re- 
sult in passing b\ the target. On a 
first-finder-wins hunt, you wUJ 
lose valuable minutes while try- 
ing to find a turnaround. On a 
hunt scored by odometer mileage, 
one slip could mean the difference 
between first place and a much 
poorer showing. 

Along straight city boulevards, 
it's easy to detect a small shift in 
the bearing as you swing your 
two-meter vagi or quad. The usual 
poinler-and-compass-rose indica- 
tor on the mast bottom is all you 
need. Bui what about those me- 
andering streets through new resi- 
dential neighborhoods? In my 
area, they are seldom straight or 
aligned to the four major compass 
directions. 

Worse yet are roads through 
canyons and over ridges. Even 
though it is necessary on a large 
percentage of hunts starting here 
in Fullcrton* I used to dread 



Photo A. The LiteOn DCS 800 
automotive flux gate compass 
can he used to display the posi- 
tion of your mobile beam an- 
tenna u ith respect to true north. 

52 73 Amateur Radio Today * July 



Radio Direction Finding 

going over the hills from Orange 
County to the San Gabriel Valley 
on Fullenon Road or Hacienda 
Road. The hidden T might be in 
the hills or over the top. It's hard 
to tell which when the signal sud- 
denly gels strong, because of the 
many twists and turns of the road. 
There is no place to pull over on 
these two-lane highways and you 
arc subject to horns and curses 
from drivers behind you if you 
slow down to less than the legal 
limit. 

I longed for an indicator that 
would continuously show f mast 
orientation with respect to true 
north, instead of just relative to 
the vehicle heading. With it. I 
could quickly detect bearings 
shifts no matter how much the 
road curves. Let's see, a shaft en- 
coder could detect mast position. 
\ chicle heading would come from 
a digital compass or GPS unit. 
Then I would have to pui it all 
together with a dedicated com- 
puter and write a program to dis- 
play It Wait, there is a much 
easier way! Just put a remote 
compass sensor on the hand-ro- 
tated antenna mast! It directly 
senses beam heading with respect 
to north and displays it as the 
beam goes around. 

An inexpensive solution 

Several southern California T- 
hunters, myself included, have 
used Radio Shack™ automotive 
compasses as remote mast indi- 
cators for Five years or so. in ad- 
dition to the usual mast pointer. I 
have not written about it in this 
column because the model we use 
has long been discontinued by the 
Shack and was thought to be un- 
available. With help from 
N4NEQ, KE6DKF and others on 
the Internet radio direction find- 
ing (RDF) mailing list, 1 recently 
found oui that this device is still 
being manufactured by the com- 
pany thai designed it, LiteOn 
Automotive of Memphis TN. 

The model DCS 800 automo- 
tive compass (Photo A) uses 
fluxgate technology to sense the 
Earth's magnetic field and display 

1997 



the sensor orientation on a rotat- 
ing disc that you can mount in 
plain sight of ail T-hunters in the 
vehicle. It is available for less 
than fifty dollars from J. C. 
Whitney™ Automotive Supply. 
You may also find it at your local 
recreational vehicle supply store. 

The heart of this device is a 
small sensor cube, only 1 x 1 x 
0.75 inches, weighing less than an 
ounce (Photo B "}. It consists of a 
toroidal (doughnui-shaped) core 
of high-nickel steel or ferritc ma- 
terial with three windings on it. 
The bottom (control) winding 
goes around and around through 
the hole of the doughnut and cov- 
ers the entire surface of it A 2kHz 
square wave is impressed on the 
control winding, causing the core 
material to go into and out of satu- 
ration at one magnetic polarity, 
then the opposite, and so forth. 

Two orthogonal (oriented at 90 
degrees from one another) sense 
coils are wound over the core and 
the control \v Lading, not passing 
through the center hole. If there 
w ere no ambient magnetic fields, 
the alternating saturation flux 
lines within the core would al- 
ways cancel and no current w ould 
flow in the sense coils. But 
Earth's magnetic lines of force are 
"pulled into" Lhe high- permeabil- 
ity core each time it leaves the 
saturated state. This induces mo- 
mentary current pulses from the 
two sense coils in proportion to 
the orientation of the Earth's field 
relative to each. 

When suitably processed, am* 
plitude and phase values of the 
sense coil signals are sufficient to 
determine the exact orientation of 
the horizontal component of the 
Earth's field — in other words, a 
compass reading. The two pro- 
cessed signals arc called sine and 
cosine (sin/cos) outputs because 
they create sine waves 9() degrees 
out of phase from each other as 
the sensor is rotated in azimuth. 

Note that the toroid core must 
remain oriented with its central 
axis exactly perpendicular to the 
Earth's surface in order to sense 
only the horizontal component of 
the Earth's field, The compass 
sensor rotates around this axis as 
bearings are taken. Any till of the 
axis from perpendicular causes 
pickup of vertical components of 
the field, resulting in bearing errors. 



In the LiteOn compass, a spe- 
cial motor (resolver) turns to dis- 
play the heading described by the 
sin/cos signals (Photo C). It has 
two orthogonal coils within, one 
for each signal, and a display shaft 
with a magnet on it. Even though 
it turns freely when power is off, 
response of this resolver in opera- 
tion is somewhat "lumpy" or 
"sticky." That is, it does not react 
accurately to small (less than 20 
degree) changes in direction and 
it has some backlash. Normal vi- 
bration of the vehicle helps over- 
come this characteristic. 

Fluxgate compasses with 
precise digital readout and no 
backlash are available from 
Autohelm™ and KVH™, but 
ihey are considerably more ex- 
pensive. Their automatic compen- 
sation features are not suitable for 
use on a rotating mast atop a mov- 
ing vehicle, Besides, the analog 
mechanical disc of the LiteOn 
compass is far easier to read than 
a digital display when the sensor 
is attached to a manually turned 
RDF beam on a winding road. 

Put it to work 

The sensor and display are con- 
nected by a 10-inch five- wire 
cable. J. C. Whitney sells a 3-foot 
extension, but you can easily 
make your own from ordinary rib- 
bon cable, Mine is six feet long, 

There are three important fac- 
tors to consider when you mount 
the fluxgate sensor on your RDF 
antenna. First, beware of the mag- 
netic effects of your vehicle's 
body. At first, 1 was more con- 
cerned about the five-wire cable 




Photo B. The flux gate sensor is 
smaller than a ping-pong hall. 
With the cover removed, you 
can see the sine ami cosine 
windings crisscrossing the top 
a ml bottom, covered with tape- 



upsetting the opt ration of my 
RDF quad, so I mounted the sen* 
sor to a bracket on the side of the 
masi below the antenna, about 
nine inches above the roof. Ac- 
curacy and repeatability of the 
indications were poor, When I 
calibrated the sensor around the 
azimuth circle with the van head- 
ing east, the readout would be 
u roiig w hen I was driving wesr I 
moved the sensor to the top of the 
PVC mast, 28 inches above the 
vehicle roof. This solved the in- 
accuracy problem. The cable go- 
ing down the mast through the 
quad has not affected the 
antenna's directional pattern. 

Second, be sine thai Ihe bottom 
of the sensor remains level in op- 
eration. Mount it so that there is 
no lilt forward, backward or to the 
side at any setting of the mast. 
Any till will cause error due to 
pickup of vertical components of 
the Earth's field. 

Third, remember that map plot- 
ting is far simpler with true bear- 
ings than with magnetic bearings, 
As you probably know, a mag- 
netic compass does not seek out 
the geographical north pole. It is 
attracted to the magnetic north 
pole, which is near Hudson Bay 
in far northern Canada. To USA 
residents, this means that unless 
you live along a line from Indi- 
ana though South Carolina, you 
must correct your magnetic com- 
pass indications in order to have 
bearings relative to true north for 
plotting on standard maps. 

Hams throughout Florida have 
only about two degrees magnetic 
declination, as this effect is called. 
If you are in northwestern 




Photo C\ Rear view of ihe DCS 
SiH) display with the cover re- 
moved shows the two circuit 
boards. The round object in the 
center is the air-core resolver. 



Washington or northern Maine, 
the error is about 24 degrees — 
quite significant. You can find the 
magnetic declination where you 
live from a United States Geologi- 
cal Survey topographical map of 
the area. 

Here in southern California, 
declination is about 14 degrees 
east, which means that 1 4 degrees 
must be added to magnetic com- 
pass readings to get headings rela- 
tive to true north. If vou live to 
the east of the zero-declination 
line, your declination is westerly 
and you must subtract the decli- 
nation value from magnetic bear- 
ings to gel true bearings. 
Fortunately, it 's easy to mount the 
sensor so as to automatically com- 
pensate for the magnetic declina- 
tion in your area. 1 did it by 
canting the sensor 14 degrees 
clockwise on the mast, as show n 
in Photo D 

A better display 

"Stickiness" and backlash are 
artifacts of the resolver only. The 
sin/cos signals are delayed by in- 
tegrator stages, but they follow 
directions quite accurately. You 
can readily extract these signals 
and connect them to a belter indi- 
cating system of your own design- 
Drive to the resolver comes 
from integrated circuit U2, an 8- 
pin DIP visible to the left of the 
resolver in Photo C. Pin 1 is the 
sine (east- west) signal and pin 7 
is the cosine (north-south) signal. 
Maximum-lo-minimum swing of 
each signal is about 4,8 volts. 

U2 stages are voltage doublcrs 
as well as drivers. The output 
voltage range of U2 is too great 
for some applications, including 
the NorthScopc to be described 
next month. More suitable tapoff 
points are at the outputs of UK 
the stages that feed the 2x driv- 
ers, Ul is the 14-pin 1C above and 
to the right of the resolver in 
Photo C. Pin 1 of Ul is the sine 
integrator output and pin 7 is the 
cosine integrator output. Table 1 
shows the approximate Ul output 
voltages for 16 compass head- 
ings, Note thai the signals swing 
positive and negative with respect 
to a +4,2- volt analog reference 
level, which is one half of the 
+S.4-volt regulated supply line. 

Photo E shows how [obtained 
the analog signals for my 



external display. Ul outputs are 
hidden under the resolver disc, so 
I tapped the sine output at the 
lower pad of R9 and the cosine 
output at the lower pad of R19. 
The analog reference voltage and 
circuit return are also required by 
the display; they may be tapped 
at the positive and negative ter- 
minals, respectively, of CI 3. This 
100- microfarad electrolytic ca- 
pacitor is next to US on the bot- 
tom of the horizontal circuit 
board, not visible in the photo. 

A fluxgate sensor on your mo- 
bile beam's mast is an excellent 
aid to transmitter hunting on wan- 
dering roads. Next mouth's Hom- 
ing In will have the details of an 
easy way to put the sin/cos out- 
puts to work in a two-dimensional 
cathode-ray-tubc (CRT) display 

Continued 







Photo D. I a f racked the sensor 
module f(f fht j top of the Cuhex 
quad boom. Before mounting, f 
marked a line or exactly +15 de- 
grees from the boom axis. I then 
aligned the sensor with the line 
io compensate for magnetic 
declination. 



Degrees 




Sin Out 


Cos Out 





N 


4.2 


5.4 


22.5 


NNE 


4.7 


5.3 


45 


NE 


5.0 


5.0 


67.5 


ENE 


5.3 


4.7 


90 


E 


5.4 


4.2 


112.5 


ESE 


5.3 


3.7 


135 


SE 


5.0 


3.4 


157.5 


SSE 


4.7 


3.1 


180 


S 


4.2 


3.0 


202.5 


ssw 


3.7 


3.1 


225 


sw 


3.4 


3.4 


247.5 


wsw 


3.1 


3.7 


270 


w 


3.0 


4.2 


^. V> J— ■ w 


WNW 


3.1 


4.7 


315 


NW 


3.4 


5.0 


337.5 


NNW 


3.7 


5.3 



Table /, Approximate voltages with respect to ground at the sine 
and cosine tapoff s from the DCS 8(H) before the 2x resolver driver 
stages. 

73 Amateur Radio Today » July 1997 53 



QRP 



Number 54 on your Feedback card 



Michael Bryce W88VGE 
2225 Mayflower NW 
Massition OH 44646 

Last month, wc talked about 
rechargeable batteries. Lead-add 
and NiCd are by tar the most com* 
mon types you 11 encounter. How- 
ever, in the next few years you'll 
be hearing more and more about 
the nickel mcial hvdride. or Ni- 
MM, and the lithium ion batter 
ies. Let's take a look at them this 
month. 

The Ni-MH battery 

The nickel metal hydride bat- 
tery is a close relative of the NiGtL 
Tt has a very similar discharge 
curve and has the same 1 .2V per 
cell state of charge, 

The Ni-MH batten has a spc* 
cific energy thai* s about twice as 
good as a lead-acid battery. It also 
has a specific power density that's 
on par with the lead-acid battery. 
Ni-MH ban cries also have great 
cold -wcat her performance, but 



?" 4f t • ***** 



Photo E » Fn utt v ie u ■ < jf th e \ v ft i - 
ad display hoard with the fare 
plate removed. Wires have been 
added to pick up the sine and co- 
sine signals, as well us the ana- 
log return and DC ground. 

Homing in continued 

of bearings relative to true north. 
The NorthScopc is all analog — 
no software or digital circuits are 
required. Meanwhile, keep the 
letters and E-mails coming with 
your RDF projects and news of 
T-huming activities in your area. 
For more in format ion on RDF 
equipment and links toT-hunicrs 
in your area, surf over to the 
Homing In Web site listed at the 
lop of this article. Don't lorgei the 
forward slash at the end. !Z3 

54 73 Amateur Radio Today -July 



Low Power Operation 



thev don't do as well as the lead- 
acid batteries at higher tempera- 
tures — so you could see lower 
than expected results from a Ni- 
MH bauer\ if vour Field Dav oc- 
curs in a very hot location. 

-Mm*, don't be misled by some 
of the ads you see. Nickel metal 
hydride batteries do in fact suffer 

■ 

from the dreaded memory effect. 
However, it is not as pronounced 
as with the NiCd celJ. 

The Ni-MH battery has a lot 
going for iu and since no hazard- 
ous materials are used it can be 
safely disposed of at the end of 
its life. 

A point to mention before you 
drop a lot of money on new metal 
hydride batteries: Most of the old 
NiCd chargers won't like the new 
cells. If you change over to metal 
hydride, you'd better plan to 
spend money on a new charger, 
too. 

You could easily home-brew 
one of these special chargers us- 
ing the chip sets provided by 
Maxim™ as well as others. At one 
Lind two chips at a pop, they are a 
bit expensive — but a project like 
this would be a ereat one for a 
club. 

Lithium ion batteries 

You may have heard a lot about 
these guys. They are now pop- 
ping up in laptop computers, at a 



premium price. Their energy den- 
sity is much greater than the NiCd 
or the Ni-MH battery, and they 
have almost five times the energy 
density of a lead-acid battery. The 
lithium ion battery has a lot go- 
ing for it. but there are a bundle 
of problems w iih these cells. 

First, they* re expensive. It's 
quite easy to get up to ten times 
the price of a battery pack if you 
choose lithium ion cells — and 
they're very picky about how ihe\ 
are recharged. You must use a 
special charger buik./usr for these 
cells. Also, riehi now. thev come in 

■m. m 

limited cell sizes. You won't find 
large-capacity cells on the market 
Uhat you can afford) just yet. As 
production increases, you'll see 
more sizes and lower prices. 

Charging these special use 
batteries 

While wc can get by with a 
basic cheap-and-diny charge 
scheme to fill up the lead-acid 
batteries, the Ni-MH and lithium 
ion require a bit more brains. 
Luckily for us, there arc several 
companies that make special 
purpose ICs to do just that! 

Primary cells 

Although we've been talking 
about rechargeable cells, don't 
overlook the primary or one-time 
use cells. There's a lot of bang for 
the buck hiding inside an alkaline 
battery! Do you remember the old 
loom™ 1C-2AT handheld? For a 
few bucks, you could get the bat- 
tery pack that would hold AA- 
sized alkaline batteries, You could 



talk and talk on the same set of 
batteries while the other guy went 
through three NiCd packs. Best of 
all, you could buzz into the local 
stop-V-rob on the way to the 
hamfest for a pack of batteries for 
under five bucks. Of course, once 
they were used up, you threw 
them out. And all those replace- 
ment batteries do add up, both on 
your budget and in the landfill. 

RENEWAL* batteries 

Thanks to Ray-O-Vac™ and 
their RENEWAL cells, you can 
get the power of the ihrowaway 
batteries with the ability to re- 
charge them over and over. Tve 
been using the RENEWAL cells 
in sev eral sets of consumer equip- 
ment and have had very good re- 
sults. Here are some hints you 
may want to try if you plan to use 
the RENEWAL batteries in your 
QRP equipment. 

First, they really like to be re* 
charged. Don't wait till they're 
dead before sending them to the 
rechargcr. Charge often and 
they'll last longer 

They appear to like loads that 
consume current. They love CD 
players and tape players, They 
don't care loo much for low-cur- 
rent loads like radios (the old AM/ 
FM types). 

You must use the charger de- 
signed for the batteries. A NiCd 
charger will destroy the cells in a 
short time. See the March 1997 
issue of 73 magazine for a huild- 
it-yourself charger for these cells 

Next month, some antenna 
tuners and various antennas! 



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1997 






Letters 

Continued from page 7 

available at hamfests for as Little 
as $50, and they will do the job, 
A well-written DOS program will 
run perfectly on any Intel proces- 
sor from an 8088 through today's 
fastest Pentiums — and in contrast, 
way too many Windows 95 pro- 
grams run poorly on the single 
platform that supports them. DOS 
programs aJso tend to be very por- 
table for the most part. A lot of 
my ham-related programs will run 
from a single disk. I also use the 
HP 200LX Palmtop for field ops 
and mobile packet w iih some very 
smartly designed DOS programs 
since their memory footprint is 
extremely low, using less than the 
640k base, which is a standard 
part of any PC. Many of my all- 
time favorite programs are older 
shareware, freeware, and public 
domain DOS programs. They 
were designed by users for users 
and usually worked first time 
around. Features were added as 
necessary and the revision and 
upgrade numbers actually had 
meaning. The author actually con- 
ducted the debugging and beta 
testing, not the consumer out of 
his own pocket. 

3. The Common User Interface 
is Microsoft's attempt to force us 
all to work the same way. It's 
great for the three "bread and but- 
ter" applications, namely word- 
processing, spreadsheets, and 
databases, but is irrelevant and a 
very uncomfortable fit for other 
kinds of software, Tell me, for 
example, how do the basic "File, 
Edit, View, and Insert" commands 
relate to a Morse training program 
or a rig interface program? 

A. Windows 95 development is 
obviously not the bed of roses Mr. 
Carr claims. In almost every in- 
stance I can think of t the "new" 
Windows 95 versions of pro- 
grams load and run substantially 
slower than their DOS anteced- 
ents. Maybe Visual Basic 5 does 
indeed approach the speed of Vi- 
sual C, but that's just a way of 
saying how bad performance in 
Visual Basic has been since ver- 
sion 1 .0. A Turbo C program on a 
386 will beat the pants off either 
of them. How many of you re- 
member the speed of Turbo Pas- 
cal on the 286 machines? 



5. One of my biggest pet peeves 
is forced consumerism and the 
underlying implication that we 
are worthless as human beings 
unless we run right out and buy 
the 4t bcst, fastest, newest" prod- 
ucts. Companies seem to be in- 
tent on rushing poorly designed 
and poorly tested products into 
the marketplace in a seemingly 
overzcalous attempt to garner 
sales and grab the big bucks, not 
to mention the advertising push 
with a fair amount of trashing of 
other peoples' products. The poor 
consumer is forced to debug these 
products out of his or her own 
pocket, or have you noticed that 
Iomega charges nearly $15 for a 
tech support call and many oth- 
ers have instituted the pay-per- 
problem premise? Apparently, 
after surviving sufficient levels of 
frustration, complaints and 
jammed phone lines the consumer 
is made aware of a new soon-to- 
be-released version of the prod- 
uct; and, of course, the consumer 
is expected to pay for this version 
as well if he/she desires to have 
all his woes settled and have a 
program that actually works* 
More often than not, the new ver- 
sion costs more than the faulty 
one and basically all you are pay- 
ing for is a patched version of the 
old program. So, where do we 
draw the line and stop buying into 
this marketing insanity? All in all. 
there are many "excuses" for of- 
fering MS-DOS software, and 
will be for several years. There 
are very many good and desirable 
DOS-based programs still on the 
market and still available through 
various BBS or Internet sites, One 
of the neatest things about DOS 
programs is that there are no GPF 
messages and the ' l you know 
you're gonna die" Close/Ignore 
buttons. Also, the memory reserves 
aren't occupied with all the graphic 
refresh rates! What is inexcusable 
is the way we have let Microsoft 
take control of the entire personal 
computing industry. And the way 
some of us appear to have swal- 
lowed Microsoft's propaganda 

As a known Mac user, both 
DOS and Windows are beneath 
my contempt. Hey, Carr, shame on 
you for getting us involved in a 
theological argument. Leave that 
mischief to me ... Wayne. 

Continued on page 70 



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Amateur Radio Via Satellites 



Andy MacAtlister W5ACM 
14714 Knights Way Drive 
Houston TX 77083 



Satellites have been used for 
decades to send television signals 
across the continent and around 
the world. Today there are hun- 
dreds of channels of program- 
ming available from commercial 
geostationary-orbit satellites. 
With dishes as small as 1 8 inches, 
homes from urban to ultra-remote 
locations can have enormous 
viewing options: main amateur 
radio operators have often won- 
dered why there are no hamsats 
for TV. 

Full-motion, real-time, analog 
television is a verv difficult mode. 
For terrestrial ATV 1 amaieur tele- 
vision) enthusiasts, high power, 
big antennas, quality coaxial 
cable, tow-noise preamps and 
wide bandwidth are required to 
work TV. ATV repeaters help dra- 
matically, the same way FM voice 
repeaters allow fringe and low- 
power stations to communicate 
across large distances. 

A repealer in orbit would be 
great, but there arc a few prob- 
lems. The bandwidth forearlh-lo- 
space or spacc-to-earth ATV is not 
available in the VIIF and UHF 
regions; thus the lowest frequen- 
cies available for use would be the 
1260-1 270MHz satellite uplink 
band and the 2.4GHz satellite 
downlink range. Another problem 
is convincing the satellite build- 
ers that an OSCAT (Orbiting 
Satellite Carrying Amateur Tele- 
vision) would be a good idea. 
Most of the technical wizards who 
design and build the hamsats 
agree that full-motion TV is pos- 
sible, hut describe solutions thai 
are digital in nature and require 
special modems and video com- 
pression methods. This would 
need special gear for the earth- 
bound user but would allow the 
"video" to be sent in a narrower 
bandwidth. Good quality analog 
FM ATV would require at least 
10MHz, while digital compres- 
sion modes could take less than 
I MHz for similar results. 



SSTV from orbit 

Only 10 days after the launch 
of AMSAT-OSCAR-6 in October 
1972, Don Miller W9NTP wrote 
a letter to the editor of the . WIS AT 
Newsletter describing his efforts 
with WA9UHV to send SSTV 
(slow-scan television) images via 
the new satellite. 

In his letter Don described sys- 
tems that included equipment that 
might be found in a ham radio 
museum today, but 25 years ago 
represented state-of-the-art gear. 
I IF trans mi tiers with trans verters 
and home -brew video samplers 
and modulators provided uplink 
signals while more home-brew 
equipment was used to view 1 the 
black-and-white images sent 
through the Mode "A" (2m up and 
10m down) transponder These 
pioneering efforts have provided 
inspiration for today's video ex- 
periments and some exceptional 
possibilities for the future. 

In his mid-seventies book, OS- 
CAR Amaieur Radio Satellites, 
Stratis Caramanolis recounted ef- 
forts by DL8AT and OE3KMA to 
send SSTV pictures via the Mode 
% *ET (70cm up and 2m down) tran- 
sponder on AMSAT-OSCAR-7. 
The year was 1976 and eight-sec- 
ond, black-and-white pictures 
were still the standard. These ef- 
forts let! to additional image trans- 
fer techniques including facsimile 
i FAX) transmissions by DL0VB 
and others. 

Digital pictures 

During the 1980s* emphasis 
was placed on the purely digital 
modes like AX. 25 packet, Today 
we have several digital -only sat- 
ellites in orbit capable of provid- 
ing worldwide store-and- forward 
services. Sending image files of 
all types via these electronic bul- 
letin boards in the sky has become 
common. Moving pictures like 
-MOV, .AVI and animated .GIF 
files have also been uploaded to 
the 9600-baud digi-sats. SSTV 
real-time image exchange via sat- 
ellite has declined, but thanks to 
advances in inexpensive digital 



interface techniques and indi- 
vidual efforts, SSTV operation 
gained some popularity while 
AMS AT-OSCAR-13 was in orbit 
Dave WB6LLO hosted an SSTV 
net on the satellite on a regular 
basis. 

With sufficient data transmis- 
sion speed (requiring wider band- 
width), experiments with com- 
pressed and digitized video will 
be possible through Phase 3D. 

SAREX, SSTV and ATV 

Dr. Tonv England W0ORE 
took the Shuttle Amateur Radio 
Experiment (SAREX) equipment 
into orbit on the shuttle Chal- 
lenger in August 1985, Part of the 
ham gear included a modified 
ROBOT 1200C scan convener 
for SSTV. The image-control 
software on the shuttle supplied 
automatic sequencing, providing 
two red- filtered frames (right 
see.), one green, one blue* a low- 
resolution color frame (12 sec), 
and a high-resolution color image 
(36 sec), Many stations moni- 
lured the signals using home- 
brew SSTV systems or new and 
expensive ROBOT equipment. 
Others simply recorded the war- 
bling tones in hopes ol someday 
decoding the cryptic sounds and 
viewing the pictures. Further ex- 
periments with SSTV from the 
shuttle continued on missions 
ST5-37, STS-50 and STS-56. 

In addition to sending pictures 
earthward, the shuttle apparatus 
can also receive and display im- 
ages sent from earthbound hams. 
During Tony England's flight, a 
picture of the astronauts* wives 
was sent up to space and dis- 
played or one of the monitors to* 
cated in the aft crew station, The 
picture was stored and sent back 
to Earth a few minutes later. 
During STSoO. schools with 
suitable SSTV gear sent pic- 
tures of the students up to Dick 
Richards KB5S1W and the other 
ham crew members on board the 
Columbia. 

There are advantages and dis- 
advantages to shuttle-based 
SSTV operation. On the plus side. 
the signals are sent via two- meter 
FM transceivers. Signals are 
strong and color errors caused by 
frequency shift experienced using 
SSB is not a problem. The great- 
est disadvantage is the length 



o\~ time available for picture ex- 
change. Shuttle passes are usually 
very short. 10-15 minutes. The 
ROBOT equipment is capable of 
1 72-second mode, but images are 
usually sent in the 3 6- second 
mode to allow the exchange of as 
many pictures as possible. The 
ROBOT gear is also limited to 
those ROBOT modes hard-coded 
in the scan converter. More SSTV 
activity is expected for future 
SARF.X tlighls. 

Later FSTV (fast-scan TV) ex- 
pcrimenis to uplink standard 
70cm ATV video to the Space 
Shuttle required FCC permission 
t»>r participating stations to send 
GMHz-wide signals to space. The 
70cm satellite uplink band is nor- 
mally only 3MHz wide. While the 
experiment worked for the few 
stations with high-gain antenna 
systems, high power and the FCC 
waiver, the activity will probably 
not be repeated, A move to higher 
frequencies and something belter 
than the inside-thc-window 
antenna will be needed DO allow 
general ham involvement. 

Mr and ATV 

While the principal ham activi- 
ties of the Mir crew are via FM 
voice or packet, there is also the 
SAFEX (Space AmateurFunk Ex- 
periment) repeater system. It was 
developed in Germany and then 
sent to the Mir space Station. The 
primary unit is a 70cm in-band 
FM voice repeater, but the second 
radio unit (for later installation) 
includes a erossband linear tran- 
sponder with a 1265 Mil/ input 
and a 2410MHz output. While use 
of the 70cm voice system is 
geared more toward "normal* 
ham operation, the L/S-hand 
(1 2GHz/2.4CHz) system is an 
experiment designed to test tech- 
niques thai may become more 
prevalent on future manned mis- 
sions. The microwave transpon- 
der is I0MH/ wide using an IF 
(Intermediate Frequency! in the 
70em band. J'h is bandwidth is 
capable of passing high-speed 
data or even television signals. 
The ATV group at the University 
of Bremen was tasked with the 
design and construction of many 
of the L/S-band components. The 
wide bandwidth of the transpon- 
der is sufficient to pass most AM 
or FM ham TV signals. 



56 73 Amateur Radio Today • July 1997 



Number ST on your Feedback card 



Hboue & Beyond 

VHF and Above Operation 



C. L Houghton WB6IGP 
San Diego Microwave Group 
6345 Badger Lake Ave. 
San Diego C A 92119 
E-mail: [clhough@pacbell.net] 

More on making silk- 
screened PC boards 

J hope I gave you some insight 
last month on making PC boards 
such as the 3 -band feed. Maybe 
this has whetted your appetite for 
more home PC board construc- 
tion. This month, 1 want to give 
you more detail about the materi- 
als and methods used. 

Alternatives 

First, let's go over some alter- 
natives to home PC board con- 
struction. Number one would be 
to go to a commercial board fab- 
rication house. I have been told 
that charges for such a venture can 
go into the hundreds of dollars for 
the first run of a dozen PC boards 
or so. This is so that the produc- 
tion house can recover their 
initial setup costs. Board produc- 
tion runs after this initial setup can 
run in the under-$10-per-board 
cost range, depending on board 
complexity, 



An alternative more in the ama- 
teur radio scheme of things, yet 
still using a commercial opera- 
tion, is to use FAR Circuits, FAR 
specializes in amateur radio 
projects and has been providing 
PC boards for projects published 
in many amateur radio maga- 
zines- They also will do custom 
work a l very reasonable prices. If 
you want to take this route and 
have artwork ready for board pro- 
duction, contact FAR for a quote. 
Their address is FAR Circuits, 18 
N 640 Field Cu Dundee IL 
60118. Send an SASE or call 
(847) 836-9148 for voice mail or 
FAX communications, 

If you are on E-mail t FAR 
Circuits can be contacted at 
[farcir@ais.net]. They also have 
a home page at [http://www.cl 
.ais.net/farcir/ 1 for board listings 
and details. They are very reason- 
able and offer a quality product 
that you might want to take ad- 
vantage of for amateur-only board 
production. 

Make your own 

What arc the benefits of mak- 
ing your own PC boards? I started 



Hhmsrts continued 

At 2410MHz, a signal can ex- 
hibit over 100kHz of apparent 
drift from AOS (Acquisition of 
Signal) to LOS (Loss of Signal) 
during an overhead pass. While 
SSB (Single SideBand) or CW 
(Continuous Wave) operation 
through the transponder will be 
a significant challenge, the 
wideband nature of TV will not. 
Automatic Frequency Control 
(AFC) circuits can deal with the 
tremendous frequency shift, al- 
lowing the receiver to lock in and 
hold the signal after initial tuning. 

Why not OSCAT? 

If the results of the Mir US- 
band transponder are promising, 
interest in producing a dedicated 
OSCAT may take hold. Most 
hams collect high-tech electronic 



devices, including camcorders, 
VCRs, and other video-related 
devices. An orbiting satellite ca- 
pable of receiving and retransmit- 
ting ATV signals may be just the 
thing to spark the interest of many 
hams who have not even consid- 
ered hamsat operation. It will cer- 
tainly be a new challenge for 
dedicated satellite chasers. A 
microsat-type unit with receivers 
for command and L2GHz video 
input, coupled with a transmitter 
for 2.4GHz video downlink, can 
be the starting point for the pro- 
gram. AMSAT (The Radio Ama- 
teur Satellite Corporation) has 
already developed the spaeefrarne 
for this type of hamsat including 
batteries, solar panels, control 
systems and antenna placement. 
Single-channel FM satellites 
work — why not television? 



to make PCBs back in the late 
1960s when I was quite involved 
in iraffic handling using teletype 
machines (RTTY) for the Navy 
MARS (Military Affiliated Radio 
Service) program. In this effort, I 
was assisting in running a small 
parts bank distributing surplus 
component parts to Navy MARS 
members in the five western states 
as part of the 1 1th Naval District 
MARS program. 

In this Navy MARS endeavor, 
I wanted to find an inexpensive 
method of producing PC boards 
to distribute for free with kits of 
component parts for AFSK (au- 
dio frequency shift kcyers) and 
for RTTY converters. The push to 
RTTY operation meant a vast 
improvement in message han- 
dling when stations were teletype 
capable. 

Getting started 

Since the boards were provided 
for free and we did not have deep 
pockets, an economical method 
had to be found to produce them. 
This assumed that we had a nega- 
tive of a board ready to start the 
silk- screen process. The negative 
was then transferred photograph!- 
cally to the screen material on the 
silk- sere en frame. 

There are several methods you 
can use to make a negative for 
silk-screen processes. The nega- 
tive that is produced can be used 
not only for silk-screening, but 
also for many other methods as 
well. 

The highest-quality result from 
a detail in copper on the PCB 
comes from the photoresist 



method. I had to pass over this 
method, though, as the setup cost 
was a little too high for the initial 
investment in material. When I 
looked at this method, the spray- 
on photosensitive resist and pre- 
sensitized PCB materials were too 
expensive or not of high enough 
quality for me to be interested in 
them. 

Pre -sensitized PCB stock was 
a major cost, with boards priced 
at $ 1 for a small 4- x 6-inch one. 
Our efforts to hold down costs 
readily sold me on silk-screen 
printing. 

Materials 

Materials needed for silk- 
screen printing include: 

• A few wooden frames to hold 
the screen mesh. J constructed 
frames 1 2 inches by 1 8 inches out 
of 2-inch-square frame stock (cut 
from 2x4s). 

• Silk-screen mesh at $8.50 a 
yard. 

• Nasdar™ Circuit Black #211 
ink, $1L75 a quart. 

• A quantity of paint thinner and 
lacquer thinner. 

• Several rolls of paper towels 
(plain white). 

• UV-light-sensinve contact 
silk-screen film, manufactured by 
tJlano Corp,, 225 Butler St., 
Brooklyn NY 11217. My cost was 
about $50 for a roll of film 40 by 
1 50 inches long, which should be 
a lifetime supply. 

• Hydrogen peroxide, from any 
grocery or drug store. 

■ Wooden work block (see below). 

• Block Out™ water-soluble 
glue. 



GROOVE FOG RUBBER RIBBING 



CONSTRUCT FRAME USING 

45 DEGREE CORNERS 

PIN VWTH 1/B - DOWELS 

GLUE AND NAIL 




MAKE 2 CUTS 

V2- DEEP X 1/8" WIDE- 

FOR RIBBING 



JL 



ON CENTER 
LINE TO MAKE 
2 2x2s 



^ 



w 



? 



FIVE FOOT KILN DRFED 2*4 



Fig. 1. The bottom of the silk-screen frame construction, showing the 
wooden frame groove and rubber ribbing that will hold the fine-mesh 
screen material in a firm* taut position. The cloth is stapled on the 
outer edge and then taped over to prevent fraying and loose threads 
dangling* Frame is constructed from kiln-dried 2x4 stock cut into 2x2 
pieces* 

73 Amateur Radio Today * July 1997 57 



■ Rubber ribbing used lor alu- 
minum screen-door repair 

• Good-quality, heavy-duty, 
waterproof masking tape. 

• Rubber squeegee 

The process 

You start by contact-exposing 
the film to your negative in bright 
sunlight or high intensity UV 
tight, I use bright sunlight of one- 
minute duration. The film can be 
handled in normal room light for 
several minutes with no ill effects. 

Mix two parts water to each 
part hydrogen peroxide and de- 
velop the film for one to two min- 
utes. 

Now the critical step. Have a 
mildly aerated supply of luke- 
warm tap water running before 
removing the film from the devel- 
oper. A small, scrap PCB can be 
used as a fiat plate to put the film 
on under the running warm wa- 
ter. 

Make sure that the film is al- 
ways covered in water while you 
rinse it. After a short while, you 
will sec contrast between the film 
removed and what remains on the 
vellum backing of the film, show- 
ing you the pattern to be trans- 
I erred to the silk-screen frame 
mesh. 

Prior to starting the film wash- 
ing, you wain to make sure you 
have a wooden work block of a 
size larger than the entire film 
being developed. Alter rinsing, 
the film is laid on lop of this 
block. In the meantime, the screen 
is at the ready, its mesh being 
slightly moistened with warm 
tap water. Now the critical point: 
The film being rinsed is ready 
to attach to the frame when the 
pattern is clear enough where 



appropriate to pass ink through 
yet still the color of the original 
film (red) in protected areas. 

At this lime, remove the film 
quickly and place it face up on the 
wooden block. Place the silk- 
screen frame on top of the film 
and block. The frames wooden 
edge dangles in midair around the 
block of wood, forcing contact of 
the screen mesh into the soft red 
transfer film and embedding the 
red film into the threads of the 
frame's screen mesh. 

Assist the drying of the pattern 
by placing a paper towel on it and 
pressing gently to assist in embed- 
ding the film into the threads. A 
very easy touch is required here, 
as a hard one will distort the origi- 
nal pattern and cause it to mush- 
room out of shape. When the 
transfer film is dry, the Mylar 1 * 1 
backing is removed. It should 
come off easily. If there is any re- 
sistance to peeling this backing 
off, let the film dry for a another 
half hour or so. 

When the backing is peeled off, 
a water-soluble glue called Block 
Out is placed on the screen frame 
on the outer edges of the transfer 
film. Be careful not to get any on 
the transfer film pattern. It goes 
on the edge of the film because 
this forms the final barrier to ink 
passing through other parts of the 
screen that are noi protected by 
the transfer film. Only the parts 
to be printed on the copper PCB 
show through the screen without 
obstruction. 

Frame construction 

The cost for kiln-dried 2x4 
wood to make wooden 2x2 frame 
members to hold the silk-screen 
<really nylon) material is quite 



SOLEEGE 




6-8* WIDE 




USE SQUEE06E WITH 

WOODEN HANDtE AND 

HARD RUBBER BLADE 

BIADE MUST BE WIDER THAN 

PC BOARD 



SJtKSOS EN FRAME 



*£- 



PC BOARD 

M0UN7ID TO 
WORK PLATE 



PLYWOOO WOftK PLATI 



Fig. 2, Front view of silk- screen printing shows rubber squeegee 
pulled over the pattern on the screen material to draw ink along 
inner frame over the pauern for deposit onto the PC board. 

58 73 Amateur Radio Today * July 1997 



SPACER 



SILK SCREEN FRAME 



1 



14 



HINGE 
SPACER 



] 



PLYWOOD WORK PLATE 



Fig* 3. Side view of silk-screen frame shows hinge to lift frame for 
board insertion and spacer w allow a small space between bottom of 
screen material and top of PC board* This ensures that contact with 
the PC board will he only at the edge of the squeegee as it is pulled 
along the length of the PC board pattern on the silk-screen frame . 



low. The other related frame ma- 
terials needed are the rubber 
screen-door repair ribbing used in 
aluminum screen-door replace- 
ment and a good-quality, heavy- 
duty masking tape. The eosi o\ 
these items is minimal. 

Haxe the 2\4 material precut 
into easy lengths to work with, 
say, five feci long. Cut a groove 
into the front face about half an 
inch from each edge. This groove 
is wide enough to be a tight fit for 
the rubber screen door ribbing 
when it is pushed into the groove, 
You don't want this to be very 
light — just sufficient to hold 
the screen taut when stretched 
and held in place with the aibber 
ribbing. 

The screen 

The groove width is usually 
about 1/8-inch wide. See Fig. 1 
for the groove and the method of 
using the rubber ribbing to hold 
the nylon screen material to the 
wooden frame. The rubber rib- 
bing is pushed down into the 
groove to lighten the screen ma- 
terial quite taut, but it's not so 
tight as to rip ihe nylon fine-mesh 
screen cloth. 

When the material is tight. i) 
will show signs of stretching 
when the middle is pushed with 
your finger We just do not want 
to see any wrinkles in the mate- 
rial. When the screen is taut, 
staple along the outside edge of 
the cloth screen material to the 
outer wood strip on ihe wooden 
frame outer edge. Any excess 
cloth on the outside of the frame 
may be cut away. After excess 
cloth is removed, a paper tape or 
good-quality cloth waterproof 
tape can be used to hold the cloth 
edge to the wood frame end to 
prevent fraying and anything 
from catching the cloth on the 



surface of the frame. This surface 
is the bottom of the finished 
frame. 

Turning the frame over, a simi- 
lar smaller- width piece of tape is 
placed on the inside edge of the 
cloth mesh, with the outer edge 
on the inside of the box bottom. 
This tape will prevent the inks and 
solvents used in the silk-screen 
process from working their way 
under the tape and cloth at the 
edge of the inside of the frame. 
See Fig. 2 for a look at the inside 
view of the frame. Fig- 3 shows 
a side view depicting the hinge 
at the rear o( the frame, which 
allows the frame to swing up for 
removal of the old blank or place- 
ment of a new one beneath the 
frame, 

Ink time 

Nasdar#21 1 Circuit Black ink 
is then placed in contact with the 
upper screen. It will imi Mow 
through the fine mesh unless the 
squeegee draws it and pushes it 
across the pattern. If you want, 
you can place a piece of paper 
on top of your circuit board prior 
to actually printing on copper. 
This makes a lest print to see how 
well you can transfer {print) the 
inks onto the paper and what level 
of detail you have been able to 
retain. 

Scrounging 

Welt there's a preliminary run- 
through of the major steps of PC 
board silk-screening from an in- 
expensive point of view. Oh. yts: 
Where can you look for PCB 
material, particularly at low cost? 

For amateur scroungers, the best 
way is to locate a PC board fabri- 
cation house somewhere in your 
area and try to purchase scrap 
pieces of copper board. They 
usually have large quantities of 



Hum to hrm 



Number 53 ait your Feedback card 



Dave Miller NZ9E 
7462 Lawler Avenue 
Miles IL 60714-3108 
E-mail: [drnillef14@juno.com) 



Please keep your ideas, tips, 
suggestions and shortcuts coming 
my way, either by "actual mail" 
or cyhcr-mail. "Ham to Ham" is 
a reflection of your interests and 
input, and its content is only as 
good as I he support that 1 receive 
from you, the reader So send your 
tips to either of the addresses 
shown above and there's a very 
good chance thai they'll appear in 
one of the future columns. 

They're not just for PCs 
anymore! 

With the current widespread 
use of multimedia PCs (personal 
computers L the availability of 
some pretty nice- sounding mul- 
timedia speaker/amplifier units 
also exists. These speaker/ampli- 
fier units are often available 
at hamfests. eomputerfests, or 



Your Input Welcome Here 



discount outlets at very attractive 
prices, and we hams might well 
consider their use in other areas 
of our hobby- — they're not just 
for use as multimedia PC sound 
drivers anymore! 

PC speaker/amps can, for in- 
stance, be used in a noisy mobile 
environment to augment the 
sometimes diffieutt-to-hear audio 
from an amateur-band hand-held 
portable transceiver or a portable 
scanner receiver. They can also be 
used within the home station to 
boost the audio from an amateur 
receiver, transceiver, DSP unit, or 
other audio source that might 
need just a bit of extra oomph. 

Many of these PC speaker/am- 
plifiers wiJI operate quite satisfac- 
torily from their own internal 
battery power, but if you'd like to 
supply longer-term DC power 
from the I2VDC cigar-lighter 
outlet in your car. or a small 
1 20 VAC-to-low- voltage- DC 
adapter in your home shack, 
then you may need to consider 



miscellaneous sizes or end cutoffs 
that are lying around, doing no one 
any good. Oiler to pay double scrap 
value, and ask lor a break because 
you are looking for PCB material 
just to make homemade boards for 
your amateur radio hobby. 

Let the PC board house know 
this is not a commercial venture. 
And if you are allowed the cour- 
tesy of digging in their scrap bin, 
use Leather l t I^\ e^ so you don* t get 
cut, and leave the area cleaner 
than when you found it. This will 
give you the best shot at permis- 
sion to scavenge again. 

The small circuit board mate* 
rial that I usually find is in 12- by 
12-inch pieces and smaller, usu- 
ally with some small predrilled 
holes in a corner from an error in 
production. The scrap bin is usu- 
ally filled with sizes suitable for 
amateur circuit boards — and then 
some. To locate these shops, look 
in the Yellow Pages™ under 
Printed Circuits, Silk-Screen 
Printing, or Wholesale Suppliers. 

Thai's it for silk-screen methods 



for now. Next month, I want to get 
into a good shakedown test you 
should make before you use your 
portable microwave transceivers. 
What we will both go through is 
the pre-test in the shack prior to 
portable operation in August's 
ARRL 10GHz Contest. Hope to 
see you on 10GHz soon. Please 
note my new E-mail address at 
the top of the column, as 1 have 
shut down the AOL operation. 73, 
Chuck WB6IGP 

Editor's note: No mention of 
homemade PC boards would be 
complete without pointing out 
Kepro Circuit Systems, Inc., 630 
Axminister Dr., Fenton MO 
63026-2992; teL (800) 325-3878 
fin St, Louts, (314) 343-1630]; 
FAX (314) 343-0668. They offer 
a wide variety of products and 
kits, as well as a free catalog and 
free "how-to" booklet. Also, The 
Meadowlake Corp., RO. Box 
1555, Oneco FL 34264, offers 
a specialized iron-on film for 
PCB do-it-yourselfers. Write for 
further information. 



CI 

M 317T 



TAB 5 AT 
OUTPUT 

FOT&JTIAL 

PfiOViI>E ADGOLATF 

HEAT^JKJNG 



Dl 

iseetexij 



1NWT 





otnwT 



Fig. 1. Basic variable regulator circuit using an LAf-5 1 IT regulator 
IC. Adequate heat si tiki fig must he provided for the LM-H7T depend- 
ing on the voltage and current to be handled by the device. Tab is at 
output potential. *D/ is needed only if there exists the possibility of 
hack-feeding a voltage higher than the output voltage. There will be 
an additional 07V drop across diode Dl. 



building a little circuit something 
like the one shown in Fig. I. 

The schematic diagram of Fig, 
1 shows an adjustable low volt- 
age regulator that can be easily 
constructed on a small piece of 
perfboard, or even by directly 
wiring to the terminals of the 
regulator chip itself It utilizes an 
easily obtained LM-3I7T regu- 
lator in a TO-220-siyle case 
i available from several of 73*$ 
advertisers), which will handle an 
amp and a half of output current 
(when properly heat-sinked), and 
up to 32VDC input voltage (the 
input must be DC, not AC), It 
then regulates that higher- voltage 
DC down to 3 V, 6V, 9V, or 1 2V 
lor anything in between) for pow- 
ering your PC speaker/amplifier 

Note (in Fig, 1) that you may 
elect to make the regulator cir- 
cuit either variable (by the use of 
a 5k pot for Rl) or fixed (by 
choosing a suitable fixed resis- 
tor for Rl from Table 1 1. If you 
don^t intend to ever change the 
voltage, the fixed resistor option 
is the best choice because it will 
never change by itself (such as 
might happen were the pot to 
become "noisy"), and it's a bit 
less expensive to build it with a 
fixed resistor than it is with a 
variable potentiometer. 

Whatever source of power you 
end up using, it should be reason- 
ably well-filtered (so that audible 
hum isn't a problem), and it 
should, of course, be able to sup- 
ply the current needed by the 
speaker/amp with some overhead 



margin for safety. It must also be 
of positive polarity. Other than 
those precautions, you should 
find the circuit pretty much uni- 
versal in its application. You 
might also find that you can run 



Fixed Resistor Values 




for Rl 


13012 


2V output 


31012 


3V 


490S2 


4V 


66012 


5V 


840£2 


6V 


1 ,02012 


7V 


1,200S2 


8V 


1 ,37012 


9V 


1 .55012 


10V 


1,73012 


11V 


1,90012 


12V 


2.070S2 


13V 


2,25012 


14V 


2,43012 


15V 


2,60012 


16V 


3,00012 


17V 



Table 1. Approximate fixed resis- 
tor values for Rl in Fig. 1 if the 
variable option is not needed, 

73 Amateur Radio Today • July 1997 50 



SO-239 
OONNtCTOR 



BaT 




ADD 

LONGEfc 

Sftfl. BRACKET 




sn SCREW 



Fig. 2. The original and modified mmklip mounts described in text 

byADSX. 



two or more speaker/amps off one 
regulator module— again, de- 
pending upon how much current 
is drawn by each, Just be sure to 
stay safely under the L5A maxi- 
mum limit of the LM-317T and 
ensure that the chip is provided 
with enough heat dissipation mass 
so that it won't go into thermal 
shutdown (a condition wherein 
the chip shuts itself off due to too 
much heat buildup internally). 
The heat sink mentioned can be a 
piece of scrap aluminum or one 
of ihe black-colored, finned heal 
sinks sold specifically to fit TO- 
220-style chips. Silicone grease 
should be used between the chip's 
tab and the heat sink mass for the 
best possible heat transfer char- 
acteristics (and to prevent *'hot 
spots" on the chip's case). 

With the LM-317T, just be 
careful not to allow the heat sink 
tab (or anything connected to it) 
to come into electrical contact 
with common ground. The tab on 
the LM-317T is at output poten- 
tial electrically, so it must be iso- 
lated from the circuit common 
connection (negative DC lead). 

The regulator chip has some 
built-in safety modes— protection 
against overheating (as men- 
tioned) and short circuits (should 
the output circuit be accidentally 
shorted). One thing that these regu- 
lators won't tolerate is back-feed- 
ing a higher \ outage into their output 
lead. This could happen if a battery 
puck of higher voltage is connected 
to the chip's output (without a 
blocking diode to prevent feeding 
the voltage back into the regulator) 
or if you accidentally connect the 
regulated bus across another higher 
voltage circuit bus. I've seen regu- 
lator chips literally explode with a 
bang (and in many flying pieces > 
under these conditions! Diode 
Dl on the schematic provides the 
necessary protection. 



With proper use, however, it 
isn't difficult at all to incorporate 
an LM-317T into a universal 
regulator for powering almost any 
small accessory, including iliose 
bargain PC speaker/amps that of- 
ten surface these days. — de Dave 
NZ9E. 

Nearly FREE parts! 



From George Primavera 
WA2SCB: 'I recently encoun- 
tered a failure of the external 

speaker jack on my I com general 
coverage receiver. The jack was 
an 'Alps/ (manufacturer's name) 
component, designed for mount- 
ing directly onto the PC board. 
The small cubical plastic shell 
which serves to hold the metal 
contacts of the jack assembly to- 
gether had cracked across the top, 
rendering the little jack useless 
Knowing thai such a part was not 
the type normally available from 
convenience electronics outlets 
like Radio Shack™, 1 searched 
through the electronics mail-order 
catalogs. Unfortunately, the prol> 
lem with mail-order parts* at 
times, is that if you don't have the 
exact part number and/or the tech- 
nical specifications of the pan you 
need, you might noi gel a suitable 
replacement. Then I happened to 
look at a couple of old VCRs thai 
I had salvaged from a nearby TV/ 
VCR repair shop. 

"Most people now throw away 
their old VCRs rather than fix 
them, and I had a few of these 
" throw-away s' on hand for their 
spare parts value, A TV/VCR re- 
pair shop in my town was more 
than happy to clear their shelves 
of a couple of these lifeless 
samples just for the taking, Guess 
what? The external audio jack at- 
tached to one of the scrap VCR 
boards was an exact replacement 
part for the one needed for my 
lcom! It was even made by the 



same manufacturer, Alps Electric 
Ltd.! Looking at the VCR board, it 
then became apparent that many of 
the same passive components (ca- 
pacitors, resistors, jacks, push but- 
tons, etc.) were identical to those 
used in my lcom. When you ihink 
about iu it makes sense; why use 
different production-line compo- 
nents for ham radio equipment and 
those that are used in Japanese con- 
sumer goods like VCRs, TVs, cel- 
lular telephones and the like? While 
there are certainly some compo- 
nents—namely higher-power RF 
pans — {hat won't show up in con- 
sumer electronics, many others do. 
Some just might be waiting for you 
to use, and for significantly less than 
the parts and labor costs you would 
have to pay if you didn't do the 
work yourself! 

^One final example: My Yacsu 
FT-23R developed an intermittent 
PTT switch recently. I happily 
found an exact replacement for the 
Yaesu's switch behind the front 
panel of a scrapped Canon VCR I 
had picked up, free, at the local TV 
shop. The HTnow works just fine, 
and the cost of replacement parts 
was about as reasonable as it gets! 
So next time you need a part, you 
in ight consider looking at scrapped 
consumer electronics items- Of 
course, it's always a good idea to 
pre-test the salvaged component 
before installing it in your ham 
equipment. Some of the newer 
VCRs also make use of many sur- 
face mount components, and these 
are a ready source for chip diodes, 
resistors and capacitors which are 
often needed for modifications to 
the newer, smaller ham gear Look 
into these 'gold mines* and you 
might just save y oursel f a few hard- 
earned dollars (and not have to wait 
for the postman) the next time your 
ham rig develops a easily comet- 
able fault/' 

Moderator 's note; A man after 
my own heart! Thanks for the sug- 
gestion, George. You* it often find 
scrap VCRs, etc., at hatnfesfs these 
days as well. They're usually just a 
couple of dollars, or even free t if 
you just stick around 'til closing 
time. Many vendors would prefer 
not to ing the ''no sate"' items back 
home again. 



plastic trackball pointing device 
used on many laptops can develop 
a tendency to slip due to dust, skin 
oils, or (often) from snacks we 
tend to keep close by while using 
our computers ! I've found that 
adding some measure of texture 
to the surface &t the trackball, 
however, can help to reduce this 
slippage problem quite a bit. 

"Here's one procedure: First, 
round up a small (4" x 6~) square 
of very fine sand paper 1 used 220 
grit, but a finer grit might be even 
better. Form the sandpaper into a 
tube slightly larger than the ball 
itself, with the gritty side on the 
inside. Remove the ball from the 
computer's trackball housing and 
place it inside the tube with your 
Tingers over the ends. Now, 
shake... the tube, that is! As the 
ball travels back and forth inside 
the tube, all surfaces should be- 
come approximately uniformly 
roughened. It took about three 
minutes of shaking for a satisfac- 
tory result when I tried it. 

"This procedure leaves the ball 
rough and gritty, but we're not done 
quile yet To change tins to a smooth 
but textured surface, place a small 
amount of toothpaste in the palm 
of your hand and 'massage' the 
trackball with it, taking care to ro- 
tate the bull so that aU areas are 
equally burnished. Most tooth- 
pastes have a slightly abrasive com* 
poncnl that helps to clean tooth 
surfaces. It will do the same for the 
plastic trackball 

"Now, after thoroughly rinsing 
and drying the ball, set it aside for 
a lew minutes while you clean the 
socket. I found that regular drug- 
store eyeglass cleaner on a cotton 
handkerchief works well for this. 
Also, clean the little rubber wheels 
linn the ball rides on in the trackball 
housing itself... the little wheels that 
generate the vertical and horizon- 
tal movement of the cursor. Blow 
away any residual lint from inside 
the housing and reinstall the ball 
and its retaining ring. 

"The ball action may have a 
somewhat gritty feel now, but it 
will be far less easily affected by 
the oils and dirt that could have 
led to slippage in the future/" 



Slippery characters 



From Richmond B* Shreve, 
Jr. W2EMU: 'The shiny little 



Oops! 

From Bill Turner W7TI: 

"Oops, there goes a cup of coffee 
right across the front of your new 



60 73 Amateur Radio Today • July 1997 



ham transceiver! It's a good thing 
that it wasn't turned on, though 
you still have the unpleasant job 
of cleaning it up — but what's the 
best method? 

"Believe il or not, water i and a 
little mild detergent, if necessary) 
can ofien be the mosi effective 
method, Where I work, we wash 
PC boards each day, using a spe- 
cial detergent made for that pur- 
pose, as part of our routine 
cleaning procedures, and it works 
just fine. The key is to make sure 
that everything is thoroughly 
dried afterward, as quickly and 
safely as possible. We dry the 
washed boards in a I70°F oven 
for 30 to 45 minutes. 

"Depending on where you live 
and the amount of minerals m 
your local water, you can prob- 
ably get away widi using ordinary 
tap water for the bulk of the clean- 
ing, but always use distilled or de- 
ionized water for the final rinse. 
Distilled water is readily available 
in most supermarkets these days.., 
Perrier™ water isn't necessary, 
HI!" 

Moderator's note: Bills meth- 
ods can be the simplest and most 
effective way to handle this 
"sticky " problem! I 're used simi- 
lar procedures an really grimy 
items of electronic gear, but you 
have to be carefuL Complete re- 
moral of easily damaged parts 
may he the safest approach. Bui 
if you deride not to remove them, 
keep all water away from trans- 
formers, relays, and delicate 
meter mtwements.Isaw one of my 
power transformers go up in 
smoke, even after what I felt was 
a thorough drying, baking, and 
appropriate idle time. It was a 
high-voltage transformer for a 
monitor scope , and even the 
slightest dampness in the insulat- 
ing layers of the transformer were 
enough to cause its demise, If you 
want to skip the oven-baking step, 
the drying process can be accel- 
erated by using an ordinary hair 
dryer for a short period and! or a 
muffin fan left blowing on the 
chassis overnight. If you do use 
dry heat, watch for dark colored 
parts (black plastic panels for in- 
stance) becoming too hot, too 
quickly, 

More backlip 
From Phil SaJas AD5X: tins 



^happy mobiling" suggestion for 
hatchback owners: "So fan I've 
not been able to find anyone who 
makes a 'true* hatchback vehicle 
antenna mount. Thoueh vou can 
use something like the Comet RS- 
21 haichback/irunklip mount on 
the side of the hatchback, vou 

w 

can't use it on the top lip of the 
hatchback door. The lip of the 
hatchback drops down below the 
vehicle's roof level, causing these 
types of mourns to hit the vehicle's 
roof before the hatchback door is 
fully open; at least this is the case 
with the Chevrolet Geo, the Toyota 
Tercet and Ford Explorer hatch- 
backs that I've had experience with. 
To solve the problem, the vertical 
portion of the mount must be 
moved, at least 1-1/4 inches back 
from the hatchback lip. 

"I've had success in modify- 
ing a Comet RS-9 irunklip 
mount ^which sells for about 
$12) in this application, hy sim- 
ply making a new lip mounting 
bracket. 1 cut off the RS-9's 
original mounting lip. and 
bolted the 'modified* unit to a 
new custom-made extension 
bracket with a #8 screu. For this 
new tip-mount extension- 
bracket, 1 used a straight piece 
of steel from a standard 90° 
wood corner repair bracket 
(these corner brackets should be 
available at any well-stocked 
hardware store). I bent one end 
of the bracket into a IV shape, 
so that it would fit over the 
hatchback lip on my particular 
vehicle. Next, I drilled and 
tapped the steel bracket for #6 
set screws. I've painted the 
whole bracket assembly black. 
and the final result looks pretty 
professional, if I do say so my- 
self! You* 11 have to adapt this 
idea to your own hardware and 
vehicle clearances, but Fig. 2 
should give you a rough idea of 
the approach that 1 used." 

Good DXing 

From Torn Hart AD IB: As the 
HF bands begin to make a come- 
back, here's a tip for ferreting out 

some of those often hard-to-find 
DX QSL addresses: "Most of us 
no doubt have had the thrill of 
receiving those rare DX QSL 
cards in our mailboxes, but locat- 
ing the correct address for the 
DX station, or his or her QSL 



manager, can sometimes be prob- 
lematical. There is a way, how- 
ever, to ease the problem if you 
make enoush DX contacts to war- 
rant the outlay. The GQLIST, pub- 
lished bv John Shelton VYB4RRK 
(address; The Heritage Group, 
P.O. Box 307 J , Paris TN 38242), 
compiles a monthly listing of DX 
stations and QSL routings for $3 
per single issue, or $30 per year, 
for US mailing. They also have a 
computer disk version, a tele- 
phone BBS, and an Internet site 
for faster updates. They can be 
reached by phone ai (901 ) 641* 
0109 — tell them that you saw it 
in 73r 

Murphy's Corollary : The ready 
availability of any electronic 
component will be inversely pro- 
portional to I he absolute need for 
that particular part. 

Many thanks to the contribu- 
tors who make this column worth- 
while each month — their input is 
directly proportional to the needs 
of all of us for interesting ideas. 
This month, they include: 

George Prima vera WA2RCB 
830 Park Drive 
Cherry Hill NJ 08002 
Packet address: fWA2RCB@ 
KE3CZ.#EPA.PA,USA.NA1 

Richmond IL Shrew, Jr. 

W2EMU 
P.O.Box 149 
Bound Brook NJ 08805-0149 

Bill Turner W7TI 
21607 56th Avenue West 
Mountlakc Terrace WA 98043 



Phil SalasAD5X 
1517 Creckside Drive 
Richardson TX75U81 

Tom Hart AD I B 
54 Hermaine Avenue 
Dedham MA 02026 

Be sure to check out the "Ham 
to Ham" column's home page on 
the World Wide Web at: [http:// 
www.rrsta.com/hth |. You can also 
pick up at this site any back col- 
umns you may have missed or 
misplaced. 

Note : The ideas and suggestions 
contributed to this column by its 
readers have not necessarily been 
tested by the column s moderator 
nor by the staff oflJ Magazine, and 
thus no guarantee of operational 
success is implied* Always use your 
own best judgment h< tore modify- 
ing any electronic item from the 
original equipment manufacturer s 
specifications. No responsibility is 
assumed by the moderator or by 
73 Magazine for any equipment 
damage or malfunction resulting 
from information supplied in this 
column. 

Please send all correspondence 
relating to this column to Mod- 
erator Dave Miller NZ L >E at the 
address shown at top. All contri- 
butions used in this column will 
be reimbursed by a contributors 
fee of $1G T which includes its ex- 
clusive use by 73 Magn-ine. Wc 
will attempt to respond to all le- 
gitimate contributors* ideas Ln a 
timely manner but be sure to send 
all specific questions on any par- 
ticular tip to the originator of the 
idea, not to this column's modera- 
tor nor to 73 Magazine. 



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73 Amateur Radio Today • July 1 997 61 



HUMS WITH CLRSS 



Number $2 on your Feedback pard 



Carole Perry WB2MGP 

Media Mentors Inc. 

P.O. Box 131646 

Staten Island NY 10313-0006 

NASA helps teach science 
through the World Wide 
Web 

Just as rapid changes in tech- 
nology force us to make adapta- 
tions in our daily lives, so we 
adapt in our classrooms. The mo- 
tivational techniques we use with 
uur students must constantly be 
updated as the nature and back- 
grounds of the children we teach 
keep changing. Instead of being 
intimidated or overwhelmed by 
new technology, we must think of 
it as new and more stimulating 
ways of teaching about the world. 

J recently read an informative 
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computer. I suggest you pick any 
one of these sites to get started 
and see how your children react 
to it Always remember that if 
you're creative and persistent you 
can enrich any lesson on space 
with a ham radio contact through 
the SAREX program. Call the 
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SAREX. With the advent of 
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data worldwide. The following 
sites contain the potential for 
great learning experiences; 

• The NASA Lewis Research 
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12 homepage [http://www.lerc 
.nasa.gov/WWW/K-12] uses ba- 
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serve time on the telescope. 
Instruction is given to the tele- 
scope by the students via the com- 
puter. Images selected by the 
students are photographed and 
transmitted back to them over the 
Internet within minutes. Schools 



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from alt over the world have used 
the telescope. This site is certain 
to increase students' interest in 
and knowledge of astronomy, as- 
trophysics, and mathematics. 

■ The NASA Shuttle Web 
[http://shuttle.nasa.gov] provides 
information on past, as well as 
future, flights. This site gets busy 
when there is a shuttle up because 
it provides live audio and video 
feedback, from launch to landing 
during the mission- The Shuttle 
Web has a section on sighting 
opportunities, Educators can find 
out when and where to look 
for the shuttle or the Mir Space 
Station in various cities. 

• BAD Aircraft Design [http:// 
f or n ax. arc. nasa.gov: 99 9 9/ 
bad web/bad web. html] gives stu- 
dents an opportunity to design a 
subsonic airplane on line. The 
design has to be capable of pro- 
viding nonstop service from San 
Francisco to New York. Students 
are allowed to change wing, fu- 
selage^ engine and stabilizer defi- 
nition. Help is given on what each 
variable is and what it determines. 
The site immediately analyzes the 
decisions and outputs an image of 
the airplane, whether it would 
make the flight, its cost, and other 
information. This site is an excel- 
lent place for students to develop 
deductive reasoning skills. 

• LIFTOFF to Space Education 
[http://liftoff.msfc.nasa.gov./kids/ 
welcome.html] contains materials 
for a younger audience, NASA 
personnel volunteered their time 
to create materials using JAVA 
and FutureWave applications. 
Students can do interactive word- 
find puzzles, and an activity 
where thev find out what their 
weight would be on another 
planet. There is also a quiz that 
prints out a certificate of 
completion when the student has 
finished it. 

• NASA Quest [http://quest 
+ arc + nasagov] provides students 
the unique opportunity to interact 
on-line with various NASA pro- 
fessionals and NASA projects. 
Currently being conducted are 
"Women of NASA" Web Chats in 
which individuals can communi- 
cate with female employees 
whose careers range from techni- 
cal writer, to research psycholo- 
gist, to astrophysicist, "Live from 
Mars" follows the progress of 



NASA's Mars Pathfinder and 
Mars Global Surveyor Missions. 
An archive of past projects is also 
kept at this sile and includes 
the '^On-line from Jupiter** and 
"Live from the Hubble Space 
Telescope" modules. All these 
projects are designed to motivate 
kids to pursue high-tech careers. 

• The International Space Sta- 
tion homepage [http://issa- 
wwwjsc.nasa.gov] starts off w ith 
a countdown to the launch of the 
first assembly mission for the 
space station, Technical informa- 
tion, as well as examples and ex- 
planations of what the space 
station will be used for, are posted 
here. At this site, students are able 
via E-mail to question scientists 
working on the space station. 
Since this is truly an international 
venture, students may find ques- 
tions asked from all over the 
world. 

• The Space Educator's Hand- 
book [hUp://tomrnyJsc.nasa. 
gov/~woodfill/SPACEED/ 
SEHHTML/seh.html] contains 
the NASA Spinoff '95 book, 
Spinoffs are products or proce- 
dures developed by NASA thar 
are being used in industry or in 
the home. Some of the spinoffs 
described include a workout ma- 
chine that is taken from one of the 
first training instruments used by 
the astronauts, golf aerodynamics 
used in golf balls, rescue equip- 
ment. Ihe cordless phone, and the 
robot hand. Here students begin 
to see the process that products 
take from research to the neigh- 
borhood store, At this site, edu- 
cators will also find space comics 
and a space calendar. 

These are jus! a few of the 
NASA-created sites. NASA has 
sponsored many more educa- 
tional sites. They are all geared 
toward making math and science 
education fun and informative. 
Some others you might want to 
try are: 

• Exploring the Environment 
[http://www.cotl.ed u/ETE] 

• Volcano World [http;//vol 
cano.und.nodak.edu] 

■ Athena [http://athena.wednei 
.edu] 

Bringing modern technology 
into the classroom via ham radio 
has always been one of our goals 
as educators. Now we have 
another powerful tool! 



62 73 Amateur Radio Today • July 1997 



New Products 



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Bytemark/Amidon Now on the Web 



Bytemark Corporation 
announces that its Amidon Techni- 
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The Contact East catalog spring 
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73 Amateur Radio Today * July 1997 63 



Ytetf* 



fta*° 



Number 64 on four Feedback card 



fun 



Communications Sim 

Part 19 




Multiplexing and digital data. 



Peter A. Stark K20AW 

P.O, Box 209 

Mt. Kisco NY 1 0549 



So far, we have dealt with simple 
analog waveforms; now il is time 
to introduce multiplexing and data 
compression, and show how analog infor- 
mation can be sent through digital circuits. 

Analog signals 

Most things in nature tend to change 
more or less gradually. When you then 
convert these things into electrical sig- 
nals, they too tend to change more or 
less gradually. That conversion is usu- 
ally done wilh some sort of a transducer. 
In earlier chapters, we have already 
mentioned microphones and speakers as 
examples of transducers; though we 
didn't specifically say so, the video cam- 
eras and picture tubes of TV are also 
transducers — they also convert energy 

from one form 10 another, 

But when we say "more or less gradu- 
ally," we don't necessarily mean "slowly." 
Things in nature can change fast, loo. 
What we mean is that they usually don't 
change instantaneously. Even a bullet, fast 
as it is t doesn't disappear from the gun and 
suddenly appear in the target. It may look 
that way to us because we're slow; but it 

w 

doesn't take much to prove that the bullet 
moves through every bit of space between 

the gun and the target. It gradually moves 
from one place to another, passing through 



all the in-between places — even if that 
"gradual" motion happens pretty darn 




Fig. 1, A typical analog signal. 

64 73 Amateur Radio Today • July 1997 



Fig* 1 shows what the output of a 
transducer might be when it converts 
some physical process into an electrical 
signal. This wave might represent the 
motion of a ship, or the motion of the 
diaphragm in a microphone, or the mo- 
tion of a phonograph needle as it plays a 
record, or perhaps the light pattern of a 
TV picture. It is an analog signal, and it 
could be transmitted by any of the meth- 
ods we have discussed so far — by wire 
or wireless, by carrying it as is or by 
modulating il on a carrier, cle. 

There are limes, though, w r hen we 
don't want to transmit the signal as is; 
this could he for several reasons. One 
might be that we want to combine this 
signal with others so they can all be car- 
ried together through one wire (or one 
circuit); such combining is called multi- 
plexing. Another reason might be that 
we want to reduce or avoid degradation 
due to noise or distortion; this is usually 
done by convening the analog signal to 
a digital one. Using multiplexing, and 
using digital circuits, are two totally dif- 
ferent concepts, but they are often inter- 
mixed in some way and used together 

FDM: Frequency division multiplexing 

Without calling it that, wc have already 
discussed FDM in previous chapters. The 
whole idea of radio transmission — the idea 
of using carriers of different frequencies to 
carry different signals, all at the same 
lime — is nothing hut frequency division 






multiplexing. Each signal occupies a dif- 
ferent range of frequencies; all of these 
signals are then mixed up and carried 
through the air to your antenna; the re- 
ceiver then uses tuned filters to separate 
the signals and recover the one we want. 
Frequency division multiplexing merely 
takes a large range of frequencies, divides 
that range into smaller sections, assigns 
each signal that smaller range of frequen- 
cies, and then combines ("multiplexes") 
them together. 

FDM can also be used through wires, 
of course. When Alexander Graham Bell 
invented the telephone, he was actually 
looking for methods to multiplex several 
telegraph connections onto one tele- 
graph wire. His idea was to send the dots 
and dashes through the wire as musical 
tones of different frequencies, which 
could then be separated at the receiver 
with fillers. It was not such a bad idea. 
but the state of electronics was simply 
not advanced enough at that lime to get 
his system working, (Just as well — he 
invented the telephone instead!) 

Eventually, the telephone company it- 
self became a major user of frequency 
division multiplexing. It soon became 
obvious that it was uneconomical to de- 
vote a separate wire to carry each con- 
versation, especially between cities. So 
they developed their "carrier" system, 
where each voice signal was modulated 
onto a different carrier; the carriers were 
then combined together onto one cable. 
Their first system used plain AM, and 
the carrier frequencies were multiples of 
8kHz. For example, one voice signal 



would he modulated onto an 8.000Hz 
carrier, whose sidebands would extend 
from just above 4kHz to just below 
12kHz (since the audio went to just 
under 4kHz j. The next voice signal, 
modulated onto a 1 6kHz carrier, would 
occupy the frequency range from about 
12kHz to about 20kHz, and so on. 

This telephone company FDM method 
has now been superseded with newer 
methods, but cable TV still uses FDM. TV 
signals, each occupying 6MHz of spec- 
trum, are combined onto one coax cable 
and carried into your home. (This method 
too is about to he superseded with digital 
technology, though.) 



of 1 trillion (I0 i: ) bits per second of data 
through one fiber. 



Sampling 



WDM: Wavelength division multiplexing 

Remember lhat frequency and wave- 
length are related by the equation 

wavelength = ^^L_ 

frequency 



Thus for every carrier's frequency there 
is a corresponding wavelength (assuming 
you know the velocity at which the signal 
travels in whatever medium you are con- 
sidering). WDM or wavelength division 
multiplexing— that is, using a different 
wavelength for each signal— is therefore 
the same as frequency division multiplex- 
ing, where a different frequency is used for 
each signal. 

In optical fibers, though, the color of the 
light is generally described in terms of its 
wavelength, not its frequency. So using 
different colors for different signals — that 
is, sending several differeni light beams 
through a liber at the same lime — is re- 
ferred to by the name WDM rather than 
FDM. (Using the term "color is a bit mis- 
leading, since "color" implies something 
lhat the eye can see. whereas most practi- 
cal fiber-optic communications systems 
use invisible infrared light,) 

WDM is an extremely useful tech- 
nique with fiber optics, because it 
greatly increases the amount of informa- 
tion that can be sent through a single fi- 
ber. The bandwidth over a single light 
beam is primarily limited by the disper- 
sion in the fiber; using two or more dif- 
ferent color light beams allows use of 
the full bandwidth for each differeni 
beam. As of 1996, for example, several 
systems have been demonstrated that 
use 50 or so light beams, each carrying 
20 billion bits per second, to carry a total 



Aside from FDM and WDM, most 
other multiplexing methods involve 
some sort of sampling. Sampling in* 
volves providing small portions of a 
wave, called samples, with enough de- 
tail to allow the receiver to fill in the 
missing parts. 
For instance, consider the sentence 
H_w a„e y_uT Even though there are 
some missing letters, with a bit of time 
you can probably figure out that the sen- 
tence should read "How are you?" This 
is an example of sampling. 

Fig, 2 shows how sampling might be 
used in communications. The top trace 
shows the same waveform we saw ear- 
lier in Fig, 1. The center trace shows 
how we have removed most of the wave, 
and retained just small samples, taken at 
some periodic interval (which we will 
discuss shortly). 

In an electric circuit, however, it isn't 
possible to send these samples with 
nothing between them — something has 
to connect them together, even if that 
"something" is zero volts. The result 
might be the bottom trace in Fig, 2, 
which shows Lhat each sample becomes 
a pulse, separated by a zero-volt signal 
between them. 

Let's return to our example of "H_w 
a_e y_u?" We need to do two things to 
make sure you can correctly decode this 
sentence: ( I ) make sure that the samples 
come often enough lhat the missing 
parts between them are small and can be 
reliably filled in. and also (2) make sure 
that the samples themselves are correct. 

For instance, "H e _o_?" does not 

contain enough samples, because it 
might be misunderstood to mean 'His 
fee too?" Likewise, 'H_s a^e y_u ?" has 
a mistake and would also cause an error. 
In terms of electrical sampling, these 
two requirements mean that samples 
must be taken often enough, and accu- 
rately enough, so thai we can later fill in 
the missing pieces without introducing 
any new errors. Let's now look at these 
timing and accuracy requirements in 
more deiai 1 , 



Sampling rate 



should they be taken? 

The answer comes from the Nyquist 
Sampling Theorem: In order for the 
samples to adequately represent the ana- 
log waveform, the sampling rate must be 
at least twice the highest frequency con- 
tained in the signal. (The fine print says 
lhat the sampling rate must be ever so 
slightly more than twice as highj Look- 
ing at it from the other direction, the 
highest frequency component present in 
the analog signal being sampled must 
have a frequency less than half of the 
sampling rate. 

There's still another way to look at 
this: Consider the fastest possible cycle 
in the analog waveform; if you have 
slightly more than two samples of that 
cycle, you can reconstruct the entire 
cycle from the samples, 

A CD T or compact disc, makes a good 
example. The audio signal on a CD has a 
frequency range from 20 to 20,000Hz. 
Since the highest frequency is 20,000Hz, 
any sampling rate above 40,000 times per 
second — twice the highest audio fre- 
quency—will provide enough infor- 
mation to allow the CD player to com- 
pletely reconstruct the audio signal from 
the samples, (Compact disks sample 
44,100 times per second to provide a 
slight safety factor.) 

To understand the Nyquist Sampling 
Theorem, note that its purpose is to 
make sure that the original waveform 
can be reconstructed from the samples. 
So let's see what is involved in recon- 
structing a wave from samples by look- 
ing at a "connect the dots" puzzle like 
ihe simple one in Fig. 3, which shows 
five numbered dots to be connected. 
Most people given this puzzle would use 
straight lines to connect the dots, as in 
the top trace. But when you think about 
it, there are zillions of different ways to 



The rate at which samples are taken is 
called the sampling rale. So how often 




Fig. 2, Sampling mi analog waveform. 
73 Amateur Radio Today ■ July 1 997 65 



connect two adjacent dots— you can use 
straight lines, curves, zig-zags t curli- 
cues, or anything else that strikes your 
fancy. In other words, if the dots repre- 
sent samples of a wave, there isn't nec- 
essarily just one unique wave that can be 
reconstructed from these samples. 

But suppose we lay down two simple 
rules: 

L No sharp corners are allowed. This 
automatically rules out using straight 
lines to connect dots, because this would 
always leave a corner where two such 
lines meet at a dot (unless three dots are 
lined up in a line, which is unlikely to 
happen very often). 

So this rule means that adjacent dots 
can only be connected with curves. But 
it also puts a constraint on the curves. 
When two curves meet at a dot, no sharp 
corner is allowed between them, ei- 
ther — they must blend smoothly into 
each other without making a corner. This 
still leaves a lot of possible curves that 
w r ould fit, so we make one more rule: 

2. No sharp bends. Any curve con- 
necting two dots must be the "least 
curvy" curve that fits rule 1, In other 
words, only the smoothest curves are al- 
lowed, curves which bend as little as 
possible. Any bends in a curve must 
have the largest possible radius, 

With these two rules in effect, we sud- 
denly discover that there is only one pos- 
sible way to connect all the dots, similar to 
the bottom trace in Fig, 3- This unique 
connection is the analog signal that would 
be reconstructed from the samples. 

How do we enforce these two rules? We 
note that waves that contain a lot of tight 
curves or even corners contain very high 
frequency components {think of the square 
wave, which has right-angle comers and 
harmonics that extend way up to infinity), 
The Nyquist theorem, by saying dial the 
highest frequency in the analog signal 





Fig. 3. Connecting five dots. 

66 73 Amateur Radio Today * July 1997 



Fig. 4. Aliasing error. 

must be less than half of the sampling rate, 
puts a limit on high frequencies. 

In a very concise way, the Nyquist 
theorem essentially says this: 

An analog signal that has sharp bends 
also has high frequency components. 
This means that the sampling rate must 
be very fast — twice as fast as the highest 
frequency component in the wave- 
When you sample this fast, then the 
samples are so close together that the 
portion of the waveform that connects 
any two adjacent dots (samples) is so 
small that it doesn f t have a chance to do 
much bending. 

If the sampling rate is not fast enough, 
then reconstructing the original wave from 
the samples will lead to a type of error 
called aliasing. Fig, 4 shows an example: 
Curve A is the original wave being 
sampled, but the samples are not taken fast 
enough (Le., there aren't more than two 
samples in each cycle of the waveform). 
Curve B shows that there is another wave 
that also fits the same samples, and fits 
them better because it has more gentle 
curves and bends. Thus the reconstructed 
wave would be B instead of A, and this 
would lead to very serious errors. 

Well-designed sampling systems thus 
always contain anti-aliasing filters, which 
are supposed to remove any analog signal 
whose frequency is more than half of the 
sampling frequency. 

But filters are never perfect. In a CD re- 
corder, for example, a filter which would 
remove everything above 20,000Hz would 
also remove some of the signal below 
20,000Hz, thereby reducing the frequency 
response of the CD. This explains why 
CDs are recorded with a sampling fre- 
quency of 44,100Hz, instead of just 
40,000Hz. This gives an extra margin of 
safety, allowing the anti-aliasing filters to 
remove almost all signals above 44,100/2, 
or 22,050Hz, yet retain almost all of the 
desired audio signals below 20,000Hz, 

Sampling accuracy 

In addition to sampling an analog sig- 
nal often enough, we must also sample it 



accurately, The required accuracy depends 
on two factors — how well we need to re- 
produce the original analog signal, and 
how we intend to send the value of those 
samples to their destination. 

Let's use the compact disc as an ex- 
ample, CD specifications often list the sig- 
nal-to-noise ratio as about 96dB. This 
means that any noise, such as what might 
be introduced by slight errors in recon- 
structing the signal from the samples, 
should be 96dB weaker than the loudest 
music to be recorded. (Signal-to-noise 
measurements always use the loudest mu- 
sic so as to give the best numbers.) 

Remembering the formula tor calcu- 
lating dB from a voltage ratio, we note 
that 



„ . signal -iir 

20 og — ^ — = 96 
& noise 



Solving this for the numerical ratio, we 
get about 63, 100. Hence, if the music is to 
be 96dB louder than the noise, then it must 
have about 63, 1 00 times as much voltage. 
We will see shortly that the actual ratio 
used is 65,536, giving an actual signal-to- 
noise ratio of about 963dB. In other 
words, any errors introduced by the sam- 
pling must be smaller than about 1/65536 
of the maximum voltage, This implies that 
any voltage measurements in sampling the 
music must be accurate to at least one part 
out of 65,536 or so. 

This short calculation tells us how accu- 
rately we must perform the sampling of 
the original analog waveform to achieve a 
certain signal-to-noise ratio. But we must 
also consider how we are going to send 
these samples to their destination. There 
arc basically two approaches to do that. In 
the analog approach, we send the values as 
analog quantities. For example, we might 
use a voltage or frequency to represent the 
value of each sample. In the digital meth- 
ods, we convert the value of each sample 
into a number, and send those. This gives 
us a number of different methods. 

TDM: Time division multiplexing 

Just as FDM takes a range of frequen- 
cies and cuts it into smaller slices, so 
Time Division Multiplexing or TDM 
takes time and cuts it into smaller slices, 
one for each signal to be carried. 

The bottom trace in Fig, 2 actually 
shows one such signal, as sampled and 
converted into pulses. These pulses are 



Left 
channel 

Right 
channel 




Transmitter 



Fig. 5. FM stereo viewed as TDM. 



narrow enough that 
pulses representing 
another signal could 
be squeezed into 
Ihc empty space be- 
tween them; in this 
way, a number of 
different signals 
could be carried to- 
gether along the 
same path. 

Previously, we discussed FM stereo. We 
mentioned that the L-R, or the left-minus- 
right difference signal, was modulated as a 
DSB signal onto a 38kHz subcarrier, and 
that mairixing was used in the stereo re- 
ceiver to combine it with the L+R signal to 
produce separate left and right channels. 
But then, in just one sentence, we casually 
added that this was the old-fashioned ana- 
log approach, since modern equipment 
used a different way of accomplishing the 
same result. Because most books and ar- 
ticles describe stereo FM the older, analog 
way, many people don't understand the 
newer technology. 

The truth of the matter is that modem 
FM stereo equipment uses time division 
multiplexing! Fig. 5 shows a simplified 
diagram of how it works, The switch on 
the left, inside the transmitter, is the multi- 
plexer. It samples the two channels at a 
sampling rate of 38kHz (which is more 
than twice FM radio's highest audio fre- 
quency of 15kHz) by continuously flip- 
ping up and down. At the same time, 
another switch in the receiver (the 
demultiplexer) also flips up and down at 
the same 38kHz rate. The two switches are 
synchronized so that both are up or both 
are down at the same time; this makes sure 
that the left and right channel signals are 
properly steered to the correct output. The 
receiver then uses the samples to recon- 
struct the original waveform for each 
channel. 

The actual circuitry doesn*t use 
switches, of course; since they would not 



Left 
channel 



]_ Right 

channel 



Receiver 








M 



i 



Fig. 6. Comparison of TDM and DSB 

modulation. 



be fast enough. Transistor switching cir- 
cuits are used instead; they are synchro- 
nized by the 19kHz pilot tone. 

It is not easy to show mathematically 
that this TDM circuit gives the same re- 
sults as the DSB approach, so Fig. 6 shows 
the waveforms, developed by computer 
simulation. 

The two waveforms assume that (he left 
and right channel both contain a 1,000Hz 
sine wave, but that these two channels are 
out of phase. The sum, L+R, is therefore 
zero, while the difference, L-R, is a pure 
l t 00OHz signal. The top waveform in Fig, 
6 shows the resulting DSB signal. Since 
there is no sum signal, we have only a 
38kHz DSB signal consisting of two side- 
bands, one at 37 kHz and the other at 
39kHz, When these two are mixed, we get 
the top waveform. 

The bottom waveform, on the other 
hand, shows TDM, switching back 
and forth between the two out-of- 
phase 1,000Hz signals in the left and 
right channels. You can see that the 
bottom wave is very similar to the top; 
it just has some sharp corners, which 
could easily be smoothed out with a 
low-pass filter. 

Aside from the fact that it is cute 
to compare DSB with TDM, there is 
another point worth noting here — 




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the fact that TDM requires a sub- 
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1997): the L+R signal up to 15kHz, 
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73 Amateur Radio Today • July 1997 67 



73 Review 



Number 68 on your Feedback card 



Vintage Review: Yaesu FT-727R 

Dual-Bander 



Save money on an all-purpose HT. 



Harry M. Johnson NV7K/6 
1615 Wood Street 
Eureka CA 95501-4672 



Many new amateurs are coming 
into the hobby today via the no- 
code technician license, and most begin 
their "careers* 1 on 2m and/or 70cm FM. 
They don't have the capability that 
young hams had rn the past to pick up 
and modify surplus gear or home-brew a 
first rig. Most buy one of the many 
hand-held transceivers on the market 
and use it in its intended way as well as 
for a base station and a mobile radio. 
Even though these rigs are relatively in- 
expensive considering the value of 
today's dollar, they still are somewhat 
pricey if you arc a young person or 
someone who is also trying to feed a 
couple of hungry children. 

One way to obtain an inexpensive rig is 
to buy a good used one. Besides the need 
to know about the working condition of 
the radio, you should try to learn whether 
or not this model has Lhe ''hells and 




Photo A. Top deck controls, Yaesu FT-727R. 
68 73 Amateur Radio Today • July 1997 



whistles" that you are looking for. A daunt- 
ing task indeed, since so many models of 
hand-held FM transceivers have been pro- 
duced in the past ten years. 

The Yaesu FT-727R was one of the first 
of the dual-band amateur HTs. It can trans- 
mit and receive on the amateur 2m and 
70cm FM bands. In 1987, w r hen this radio 
came on the market, extended receive ca- 
pability was not an available option, The 
frequency coverage on two meters is 
144000-147.999MHz; on 70cm, it covers 
440 + 000-449.999MHz. The power output 
is 5W at full power on both bands and 
1/2 W on low. It is much larger than con- 
temporary dual-banders, but still a very us- 
able size at 2QQmin high x 71mm wide x 
38mm deep with attached standard equip- 
ment battery, the 12. 5 V 500mA FNB-4A. 
Its weight is 616 grams. 

Physical layout 

The controls and connection points on 
the top deck (Photo A) are; BNC con- 
nector for the antenna, VOX switch 
toggles that function on and off, mini 
phone jack for Yaesu's CAT (computer- 
aided tuning) function, mini and micro- 
mini phone jacks for the earphone and 
external mike connections respectively, 
high-low transmit power switch, lamp 
switch (illuminates LCD display) and 
squelch and on-off volume rotary pots. 

On the left side of the rig near the top 
is a bulge that houses the push-to-talk 
switches. In this case there are two distinct 
switches, one above the other, and either 
can be used. In the European model the top 
switch was the tone burst switch necessary 
to access European repeaters. The battery 
lock button is also found on the left side. 



■Jll 


M 


ft 




-- '- _ 


-— ■ 

E5s 


■ 








m— — - 


. -— pi 










---— '^S; 


hI^BS 













i 
TV 







_■•' 



Photo B. View of front 
controls, Yaesu FT-727R, 



On the right side opposite the push-to-talk 
switch is the function switch, The push-to- 
talk and function switches are covered 
with a mbber membrane which effectively 
keeps out moisture and dust. 

The front panel (Photo B) has two 
LEDs at the upper left, One is green while 
the squelch is broken and red while the 
PTT switch is depressed. The other comes 
on when the battery voltage gets below 
7.0, A very ample speaker and a mike are 
housed behind a grill. The LCD display is 
below the grill, and a 20-button keypad be- 
low thai. On the rear at the bottom of the 
belt clip and under a rubber cover is the 
VOX sensitivity switch. 

The LCD display tells you just about 
everything you would ever want to 
know, including battery voltage. AH data 
entry is done via the keypad. The D key 
puts you in lhe dial mode and allows fre- 
quency entry. Another key toggles be- 
tween the VHF and UHF bands. Ten 
memories are available between the two 
bands as well as a call memory for each. 
The keypad sequence for memory entry 
is: D, key in the frequency, M and then 
the memory number. Pressing MR puts 
you in the memory recall mode and then 
the memory number key gets your 
desired prc-cntcrcd frequency. The 
memory will hold the repealer split (+, -, 



or simplex) as well as tone encoding and 
decoding information (more on tones 
later). Each key has its primary use 
marked on it and its secondary use just 
above. By holding the function switch and 
then pressing a key, its secondary function 
is called into play. The 16 DTMF tones are 
produced by the leftmost 16 keys. A, B, C T 
and D tones are not marked on the keys 
but are generated by the keys in the fourth 
column from the left as you go down. 

The two rightmost keys on the top row 
are down and up keys, respectively. They 
will step the frequency up and down from 
the beginning setting, or when in the scan 
mode will scan the memories up or down. 
To initiate scanning, either the up or the 
down key must be depressed for one sec- 
ond and then released To stop scanning, 
press the PTT switch momentarily. 

There is a double horizontal arrow key 
to reverse the transmit and receive fre- 
quencies so you can "listen on the 
input,'* The "*" key will bring up the call 
frequency on either band. The i4 # ?? key 
followed by a memory number will put 
you into the priority mode, where a 
predetermined frequency is regularly 
checked while you're on another one. 

Special features 

The FT-727R was unique in that it was 
able to give a reading of the instanta- 
neous battery voltage to the nearest half 
volt. Using the function switch and a 
keypad press displays the voltage on the 
LCD paneL In conjunction with the red 
battery warning LED, it is a simple mat- 
ter to avoid fading off into low battery 
oblivion while transmitting. 

The VOX on-off switch on the top panel 
allows you to use a useful Yaesu accessory, 
the YH-2 VOX headset. This accessory 
did not come with the radio but could (and 
still can) be purchased at nominal cost. 
The headset is very light. It has one foam- 
covered earpad and a very light foam-cov- 
ered mike on a flexible boom. It plugs into 
the EAR and MIC plugs on the top deck. I 
have found this accessory to be extremely 
useful while traveling bicycle mobile. It 
can only be used while the rig is in VOX 
mode and, of course, the usual care must 
be exercised about what is said while in 
the VOX mode. Slips of the lip can cause 
unwanted transmissions to go out over the 
airwaves! 

A half duplex situation can be entered 
by holding the function key and pressing 



the DUP key. In this condition, you can 
transmit on one band and receive on the 
other. In certain situations this can be a 
useful feature. 

In use 

I purchased my FT-727R in May 1988 
and have been using it ever since. It. has 
at times been used as a mobile rig con- 
nected into the vehicle's electrical sys- 
tem through a home-brew adapter. Most 
often a 5/8-wave mag mount was used 
for the mobile. Most of the time was 
spent in a rural area of western Montana, 
doing rag chewing, "meaningful com- 
munication," and autopatching. In the 
absence of a base station rig it has been 
used in that capacity also, connected to a 
30 A station power supply or storage bat- 
tery and the two-meter J- pole mounted 
on the roof In that case, there wasn't 
much 1 couldn't do with the radio set at 
0.5 W. As I indicated earlier, it is used 
also in the bicycle mobile mode. Using 
either the FNB-4A battery or a small 
gel cell, it is carried in a handlebar bag 
with the rubber ducky protruding. The 
VOX headset is worn under the helmet 
and the rig placed in the VOX mode for 
operating hands-free while riding. 

Options and accessories 

After 1 had been using the radio for 
over five years, I decided it would be ad- 
vantageous to add CTCSS tone encode 
and decode capability. I purchased the 
Yaesu FTS-6 tone unit and did the simple 
installation. It worked right out of the 
box and provides the ability to use 
"toned" repeaters that I could not previ- 
ously use. The control keys are provided 
on the radio but do not function until the 
unit is installed. Also, the icon on the 
LCD panel then becomes activated. 

Early on, I unthinkingly left the radio ly- 
ing on the bed where our family cat, Spot, 
normally sleeps. She enjoyed chewing the 
end off the original equipment rubber 
ducky antenna, I ordered a very similar- 
appearing replacement dual-band ducky 
made by Larsen and used it successfully, 
Later, I came across another Yaesu YHA- 
27 original equipment ducky and com- 
pared it with the Larsen in everyday use. 
The Larsen is superior on both bands. 

An accessory that I purchased and 
must recommend very highly is the HT 
carrier called The Pouch. It is made 
of wetsuii material. The makers do an 



excellent job of stitching it up, and mine 
is like new alter almost seven years of 
use. It has a belt loop and a cover that is 
secured with hook and loop attach- 
ments. The rig has fallen several limes 
while enclosed in the protective Pouch, 
without suffering any nicks or damage. 

The 36mm speaker mounted in the 
727 case does a pretty good job in most 
situations. I purchased a Radio Shack™ 
CB-type extension speaker and mounted 
it in my car. When the FT-727R was do- 
ing duly as a mobile rig, I plugged the 
speaker cable into the EAR jack and let 
the 450mW of audio power drive the 
larger speaker for better quality. 

Summing it up 

Not all of the fid Is took place while the 
rig was safely enclosed in its protective co- 
coon. As an artist I often carry a lot of 
stuff around to various places and am not 
always careful about some of my 
armloads. On one occasion, while loading 
the car, the HT slipped out from under my 
arm and fell from above waist level to the 



"A real rock in terms of 
reliability" 

hard ground. It landed squarely on the 
ends of the squelch and volume controls, 
with the result that the squelch pot was 
broken and inoperative. I returned it to 
Yaesu for repairs. By the time it was re- 
turned, 1 had purchased the aforemen- 
tioned Pouch, which I have used since. I 
invariably hook my middle finger through 
the belt loop of the Pouch and secure the 
lop strap. That way, even though my arms 
are full, the rig cannot fall, 

I am still using the original FNB-4A 
battery that came with the radio. I have 
simply followed the NiCd command- 
ment of using the battery until it be- 
comes inoperative because of low state 
of charge and then recharging it fully. 

All in all, this HT is a real rock in terms 
of reliability. Its double conversion 
superhet receiver works well; its transmit- 
ter power is more than adequate for most 
repeater situations on both 2m and 70cm; 
it is easy to use and generally does the job. 
If you want an all-purpose, dual-band FM 
radio and want to save $150 to $2(X) over 
the purchase of a new one, look for a good 
used Yaesu FT-727R in the ads or at the 
next hamfesL 

73 Amateur Radio Today « July 1997 69 




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Letters 

Continued from page 55 

Richard Ebeling K2UTC, White Plains 

NY, My purpose for writing to you is to offer 
a suggestion pertaining to your editorials, 
I am not a subscriber to 73 Magazine, but 
occasionally read 73 via a borrowed copy. 

First, your editorials are very interesting, 
and informative; that is, there are articles/com- 
ments that I read nowhere else. My only criti- 
cism is to reduce the number of continuing 
pages that one has to turn to in order to fol- 
low your thoughts. April 1997 73 is an ex- 
ample. Starting from page 4, then page 38, 
47, 59, 61, 65, 81, 83, 88, etc, To me that is 
very distracting, plus it makes it more diffi- 
cult to keep the entire editorial. 1 do not think 
I am the only one to ask why so many 
multiple pages, but generally everything has 
a reason, 

Secondly, 1 have an observation/statement 
regarding our beloved 1 0- meter band. Are you 
aware of the "dangers" of operating 10 
meters? Probably that is not the right word to 
describe the "non-amateur mess M our band is 
in with commercial intruders, CB trespassers, 
and pirates of varied descriptions. One needs 
an up-to-date list of legal amateur radio pre- 
fixes handy. For more than one year here in 
the New York City area, we have a renewed 
NYC taxicab commercial intrusion on 10 
meters. 

Thinking back to the 1985-86 NYC taxi- 
cab invasion, it was almost unbelievable. At 
least the taxicabs do not attempt to break in 
on a 10-meter amateur QSO like thousands 
of CB trespassers and other misguided indi- 
viduals were doing during sunspot cycle 22. 
Nothing compared to the "mass invasion of 
European CBers" primarily from Italy, Spain, 
France, and other assorted countries across 
almost all of the 10- meter band, operating in 
AM, FM, and SSB mode. 

Just yesterday, with DX skip appearing on 
10 meters, already the intruders/trespassers are 
being heard, so with sunspot cycle 23 just 
starting, the 1 0-meter band will be a li chal- 
lenge" as regards how many legally licensed 
amateurs are going to be drawn into radio 
contacts with all that non-amateur trash. To 
repeat, have an up-to-date list of all legal ama- 
teur radio prefixes (domestic and foreign) 
handy. 

To someone like myself, who has operated 
10 meters continuously since sunspot cycle 
19 (through maximum and minimum sun- 
spots), it is discouraging to observe what has 
happened to a decent amateur radio band since 
the "FCC 1 1 -meter Pandora's Box." 

Well, to 10-meter beginners and old-timers 
alike: Be advised that it would be prudent to ex- 
ercise a little caution when making a radio con- 
tact, as many amateurs were completely fooled 
by non-amateur trash during cycle 22. 



70 73 Amateur Radio Today ■ July 1997 



Number 71 on your Feedback card 



The Digitrl Port 



Jack Heller KB7N0 
712 Highland Street 
Carson City NV 89703 
E-mail: [jheller@sierra.net] 

Resolving the Windows 95® 
comm port problem 

Do you ever feel as if you're 
alone in a wilderness of computer 
problems? It gets serious when 
your computer can't talk to your 
TNC. The computer I am silting 
in front of right now nearly got 
the best of me this past month. 
Logic wasn't failing; it was just 
requiring such a huge volume of 
input to gain so little. 

Let me start at the beginning, 
This computer has served me well 
for over five years with only a few 
major problems — such as the 
evening Windows 3.1® ate itself 
and the time I replaced the once- 
magnificent 105Mb hard drive 
and the tape backup lost a few 
necessary items in the transfer to 
the new 800Mb drive. 

About a month ago, the bugs 
beat down the door to their cage 
and a good working computer 
descended to the depths where 
even I was unable to help. The 
clue was when the floppy drives 
and the serial port for the TNC 
would not respond except after I 
wiggled the driver board. The final 
blow came when the wiggling pro- 
cess ceased to cure the problem and 
the parallel printer ports quit. 

I called the local computer 
gum, and prepared a list of prob- 
lems along with a list of what I 
would like to have done about 
diem while I was gone for a week. 
Fortunately, when they called to 
tell me the first logical answer 
was to erase the hard drive, I was 
still in town. It is quite exciting 
to a person like myself when a 
tech w r ants to destroy the "irre- 
placeable" files, not to mention 
numerous excellent, use-every- 
day programs. 

So, when I returned, the unit 
was nearly ready to pick up. There 
was a new r hard drive, with the 
golden files copied to one partition, 
and a nearly empty partition for me 
to fill as 1 saw fit., along with a new 
motherboard, Pentium processor 
and a whiz- bang modem. The old 



hard drive was still mounted "just 
in case something hadn't copied." 

What can go wrong win „, 

Now r about the Law ascribed to 
Murphy. I do a Jot of work that 
requires a modem to the tele- 
phone line as well as using the 
PK232 MBX. That means comm 2 
and comm 4 both need to work. You 
guessed it. Those who are up on 
interrupt requests (IRQ) realize that 
these pons use the same I RQ T In the 
past, it was necessary to exit the 
program on one port so the other 
port could be recognized. 

No matter how I explained to 
this machine that "it used to 
work," there was no understand- 
ing of my dilemma. A call to the 
computer shop revealed that the 
model of US Robotics modem 
they installed was 'plug and 
play," which is Windows 95 for 
"we'll configure it our way" — 
and I didn't have a voice in the 
matter. The answer was a modem 
from the same company with 
some jumpers that allowed me to 
set it for comm 4. 

I am one of the classic holdouts 
who kept Windows 3.1 just a few 
years longer than expected. It was 
hard enough to give up DOS. 
There are some figures, recently 
published, that show about half of 
the folks think much the same as 
I do about changing to the new 
operating system. Many changed 
back to 3. 1 after a trial run. 

In defense of Windows 95, 
once you get it working, every- 
thing runs much faster. I have 
quite a few 16-bil programs that 
really run well and faster now that 
they can take full advantage of the 
processor. Some programs just 
had to he replaced. The backup 
software for the tape drive had no 
clue what it was reading, but the 
new package makes the same 
drive perform at least three times 
faster. 

Back to the problem ... 

A ham, especially a digitally- 
minded ham, has got to do what 
he's got to do. With the ports 
straightened oui, I couldn't get the 



AEA Pack rati for W T indows pro- 
gram to access the PK232 MBX 
plugged into comm 2, The prob- 
lem looked similar to when the 
port couldn't be found. 

Follow the logical trail 

Mow do I determine the differ^ 
ence between a software problem 
and a hardware problem? Answer; 
substitution, I tried the copy of 
Winpack v6. It would give a glim- 
mer of hope and then fail. Next was 
the DOS program I referred to last 
month, it came up all right, but 
couldn^t talk to the PK232 at all. 

Maybe this is a problem with the 
PK232? I have a now ancient 386 
with only DOS (kind of nostalgic) 
that works, but the logistics (cable 
length) put ii out of reach of the 
PK232. Out of the garage came the 
MFJ 1 274, With that hooked to the 
386 and the DOS program installed, 
the two pieces of hardware commu- 
nicated fluently. That at least proved 
one piece of software worked like 
it was supposed to. 

The idea of moving the 386 
computer and the PK232 within 
cable distance of each other was 
a little daunting. Perhaps the an- 
swer was software. Maybe the old 
package [ was using so well for 
several years just wouldn't work 
with the 32-bil architecture. Back 
to the logic seat. 

I had not iced recentl y there was 
some great sounding shareware 



available. There is a copy in the 
Hamnet library on CompuServe, 
but I wanted a little information. 
I hunted down the XPWare site 
on the Internet and read through 
the claims. There were screen 
shots of the program in action and 
a DOS version as well as one for 
Windows 95. 

The descriptions convinced me 
1 had to give it a try, so 1 down- 
loaded the Windows version and 
installed ii. The program ran. 
looked very stable and seemed 
friendly enough, but when I at- 
tempted to connect to the PK232 
MBX, it spent several minutes iden- 
tifying the TNC, then locked up .„ 

Yuk. It looked so promising, 
yet I had not made perceptible 
headway, 

I looked through the User's 
Guide I had printed out and found 
that Gary Johnson KF7XP not 
only had his name displayed but 
also several ways to contact him. 
I chose the E-mail address and 
told him an abbreviated version 
of what I just told you. He got 
right back to me with a few ideas. 

After configuring the program 
for dumb terminal mode, as sug- 
gested by Gary, the program came 
up and talked to the PK232 MBX 
like they were old friends. After 
quite a bit of experimenting with 
this and other configurations, I 
was beginning to feel better about 
the hardware, but things still 
weren't nearly right 



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Photo A. Screen shot. This is XPWare in action. Actually, this was a 
day where S-meter readings were barely perceptible. I had sent CQ 
on 14.077kHz and Mike KK6YA answered. Due to conditions, the to- 
tal of the QSO shows on the screen. The link dropped before the con- 
tent of the lower (transmit) screen was sent. Note that Mike's calls ign 
automatically appears in upper left. A pop- up tog comes up with the 
automatic entries in it, hut it didn l t capture, 

73 Amateur Radio Today » July 1997 71 



'ring there was a DOS 
version of the XPWare on the 
Internet site, I went hack and 
downloaded that program. I had 
resolved that it would be worth it 
to move the furniture around in 
the shack and try an ail-mode 
DOS program from a DOS ma- 
chine, if it was going to work, 
this should do the trick. 

When it was time to transport 
the program to the 386 machine. 
1 got lazy again. It was easy to 
install in this machine and it came 
up and spoke fluently to the 
PK232 MBX — so much so that 
after a bit of fumbling with the 
new-to-me commands I made a 
FACTOR link with Doc. in Chi- 
cago (during the heat of the mo- 
ment, I didn't take proper 
advantage of the automatic tog- 
ging and the callsign is not with 
me). The signal Mrengih was in 
the just barely range at both ends 
and the link seemed flawless for 
several minutes. 1 fell like I had a 
new toy! 

A hero arrives 

So I sent Garv another E-maiL 
It was late afternoon and after din- 
ner I went back to checking this 
prc>gram, printing the 1 00- page user 
manual (I was really getting im- 
pressed with this DOS program) 
and tinkering with the packet pa- 
rameters. About 9:30 the phone 
rang and here was Gary introduc- 
ing himself. He was going to make 
this thing work. Though this wasn't 
the strangest happening in this long 
course of events, J was sure I had 
tried the settings Garv outlined. But 
when it works, Y 11 admit to almost 
anything. 

You just can't ask for much 
better service. There was some 
conversation about what 1 had 
observed since the last E-mail. 
Then he just simply led me along 
the path I should have been trav- 
eling and suddenly the program 
all fell into place. The host mode 
worked and 1 was a very relieved 
and happy camper 

A mini-review of XPWare 



For a quick review of the im- 
pressive features of the Windows 
version of XPWare, let me begin 
with how the program comes up 

with the PK232 MUX plugged 
into the serial port, On Ihe screen. 

72 73 Amateur Radio Today • July 



you can see it takes about 15 to 
20 seconds to scan and identify 
the machine, then it not only dis- 
plays PK232 MBX but also the 
latest version of ROM by date. 
There are a number of other A EA 
controllers, so the program needs 
to know precisely which one it is 
working with. 

When the operating screen is 
up, you see a familiar Windows 
formal with the s^arious available 
modes, Amlor, Baud, and Packet, 
that will allow changing modes 
and forcing transmit and receive 
functions by the logical pull-down 
menu methods. It is a nice, neat 
straightforward layout that in- 
cludes a setup menu, along with 
menus for editing text, handling 
files and excellent on-line help. 

As with any thoughtfully de- 
signed program, there are ample 
shortcut keys so the mouse is not 
mandatory for most operations such 
as making connections, changing 
modes, turning the transmit back to 
the other station, etc. But — a good 
operating mouse is useful. 

XPWare comes with automatic 
formatting for the various modes 
to do such things as call "CQ/* If 
you take a look at the screen shot 
i Photo A), the CQ sequence was 
the result of a mouse click (you 
can substitute ¥5) on the CQ but- 
ton in the tool bar. If there is no 
linkup, the program causes a 45- 
second receive time and then re- 
peats the CQ sequence. This is set 
for live complete cycles and you 
can stop it at any time. All this was 
ready to go as soon as the program 
was up and running — nothing to 
read* no codes to insert, just sit 
down and pla\. 

Somebody said recently that if 
a program isn^t intuitive enough 
to be run using the help screens* 
it is just plain bad software. 
XPWare, therefore, qualifies as 
good software by that criterion, 

I happen to enjoy PACTOR, so 
that is most of what 1 have done 
since it came up running a few 
days ago* but 1 see that jusi about 
everything that applies to one 
mode goes for the others* I no- 
ticed, to my surprise, that when I 
connected to the local packet 
node* a sweet feminine voice 
came on and not only told me that 
1 was connected, but also gave the 
calisign in phonetics. The same 
thing occurs with a PACTOR link. 

1997 



Number 72 on your Feedback card 



Spec ml euents 



Listings are free of charge as space permits. Please send us 
your Special Event two months in advance of the issue you 
want it to appear in. For example, if you want it to appear in 
the October issue, we should receive it by July 31. Provide a 
clear, concise summary of the essential details about your 
Special Event 



JULY 4 

DILLSBURG, PA The Harrisburg 
ARC will hold its Firecracker 
Hamfest 8 a,m.-2 p.m. at the 
Monagahan Fire Hall, 245 W 
Siddons&urg Rd., Dilfsburg PA. VE 
exams start at 9 a.m. Talk-in on 
146.16/76 MHz. For inlo and table 
reservations phone the HRAC 
AnswerLine at (717) 232-6087. 

JULYS 

MILTOM ONTARIO, CANADA The 

23rd Annual Ontario Hamfesf will 
be sponsored by the Burlington 
ARC, at Milton Fairgrounds, Gates 
Open 7 am to commercial vendors 
(Robert St + gate only). S a.m. to 



Is the comm port problem 
resolved? 

Possibly the strangest thing in 
all this is that which I have been 
told is impossible has occurred, 
Remember how the comm 2 and 
comm 4 cannot have the same 
IRQ and be opened at ihe same 
time? Well, these two ports have 
IRQ 3 like they are supposed to, 
and I can have comm 2 opened 
with XPWare, and connect to ihe 
phone line with my modem on 
comm 4! Honest. No tricks in- 
volved. Don't ask me to duplicate 
the magic. The wife has told me 
ail along there is a strange virus 
in this mom, I think I will have to 
join her method of reasoning. Ii 
is about as logical as anything that 
has happened during the past 
week in this I it lie room where l 
escape from the realities of life. 

If you have questions or com- 
ments about this column. E-mail 
me at [jheller@sierra.netl and/or 
CompuServe! 72! 30.1 352]. I will 
gladly share what I know or find 
a resource for you. On packet, 
when you get a chance, drop mc 
a line at [KB7NO@N7NPB.# 
NONEV.NVUSA.NOAMJ, For 
now. 73, Jack KB7NO. 



tailgaters (Robert St. gate only), and 
9 am to the public (Thomas St gate 
only). Adm: S5 per person; tailgate 
parking $2 per vehicle. The CLARA 
Annual Picnic Meeting starts at 
11:30 am Weekend camping $10 
per site. Tallin on VE3RSB 147.21 
and simplex 146.52. Contact 
Buri'mgton ARC, EC Box 85037. 
Burlington Ontario L7R 4K3 
Canada; or [ww. bigwave.es/ 
-*jefdavisfbarc/)< Or contact Jeff 
VE3COJ. (905) 335-4862; E-mail; 
[jefda vis # bigwa ve. ca]. 

SALISBURY, NC The North 
Carolina Alligators Group 'Fire* 
cracker Hamfesf 1 will be held at the 
Salisbury Civic Center, S a.m -1 
p.m. Admission is S3 in advance 
(with an SASE), or S4 at the door. 
Free to XYLs. Auction of goods will 
be at 1 p.m. Dealer setup at 6 a.m. 
Tables in the air-conditioned center 
are $5, Outside Ilea market spaces 
are free. Contact Walter (Alligator) 
Bastow N4KVE 3045 High Rock 
Rd., Gold HHi NC 28071. Talk-in on 
146,625, Directions: From I-85, take 
Hwy. #52 West/East innes St., turn 
left on South Boundary St, The 
hamfest is on the left. 

JULY 10 & 24 

FT. WORTH, TX The Lockheed 
ARC and the Kilocycle Club of Ft 
Worlii TX, will sponsor test sessions 
for all classes of licenses. They will 
be held at the Lockheed Recreation 
Area facility, 2400 Bryant Irvin Rd. T 
starting at 7 p + m. G.R.O.L. testing 
by appointment only. For info call 
Ted Richard AB50U, (817) 293- 
8745. 

JULY 12 

OAK CREEK, Wl The South 
Milwaukee ARC. Inc., will hold its 
28th annual "Swapfesf on Sat., July 
12th T at the American Legion Post 
#434 grounds, 9327 S. Shepard 
Ave.. 7 a.m, until at least 2 p.m. 
CDT. Free parking, picnic area, and 
free overnight camping are 
available. Admission, $5 per person 
includes "Happy Time" with free 

Continued on page 78 



Rduertisers' Indeh 



H.5.# page 

351 Absolute Value Systems ... 70 

68 Advanced Battery Systems 49 

■ All Electronics Corp 40 

332 Antennas West, ,«..♦. 33 

296 Antennas West * 44 

336 Antennas West 44 

304 Antennas West 46 

5 Antennas West 46 

1 35 Antennas West 67 

380 Antennas West ,.,.... 77 

16 Astron Corporation . 2 

41 Barry Electronics Corp 70 

42 Bilar Company .„ *.., 43 

163 Buckmaster Publishing 37 

56 Buckmaster Publishing ..... 30 

222 Byers Chassis Kits .... 18 

184 C & S Sales, Inc 84 

99 Communication Concepts 40 



R.S.# page 

1 Communications Specialists 33 
276 Compute r Aided Technology . 3 7 

lob Vt/UDex MintmiHHit.tii. 43 

13 Doppler Systems 77 

114 E.H.Yost 70 

8 ElMronics ■»*■«».« 36 

227 Faikner Enterprises of 

America 44 



' « *-» Vj" ^v* * E— l + l + ll + H + FI -I ■*-*■*§■ 



78 

174 

• 

42 
242 
158 
341 

86 
• 



46 



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Hamtronics, Inc CV2 

Index Publishing Group .... 67 

Indianapolis Hamfest „, 20 

Isotron , 43 

Jan Crystals .„. 18 

Japan Radio Co „*..,♦. CV3 

Kepro Circuit Systems ,.,... 31 

MFJ Enterprises 11 

Michigan Radio 7 



R.S.# page 

160 Micro Computer Concepts 44 

136 Milestone Technologies ..„ 84 

1 93 Morse Tutor Gold 46 

248 Motron Electronics 18 

248 Motron Electronics 55 

114 Mr Nicd 70 

* PC Electronics ., 55 

* Peet Bros. „ 33 

68 Periphex 49 

* Radio Book Shop .,*.,. 34 

Radio Book Shop .............. 54 

Radio Book Shop >,.... 61 

Radio Book Shop 62 

Radio Book Shop 79 

Radio Book Shop 87 

Radio Book Shop 88 

Radio Amateur Callbook ... 29 
Raibeam Antennas 49 

34 Ramsey Electronics .„... 1 



R.S.f 

254 Ross Distributing ., 
Seagon Company 



241 

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page 

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Sirio Antenna CV4 

Software Systems 

Consulting ..,. 36 

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The Mead Lady .. 31 

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Tri-Ex Tower 

Corporation ........„.„„,.♦.„.* 77 

Universal Radio 46 

VersateJ Communications , 43 

Vis Study Guides, tnc 43 

W & W Associates 73 

Warren Gregoire & 

Associates .,„ 84 

Wavemach 

Communications .......... 44 



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73 Amateur Radio Today * July 1997 73 



Rttv loop 



Number 74 on your Feedback card 



Amateur Radio Teletype 



Marc I. Leavey, M,D„ WA3AJR 
P. O. Box 473 
Stevenson MD 21153 



IdonHknow what's more sink- 
ing to me. thai this column now 
begins its twenty-first year, or thai 
my son, born the year I started this 
column, will soon murk ihe .same 
milestone. And I'm not that old, 
even though I qualified for the 
QCWA almost ten years ago! 

Through it all, as I have said 
countless times, it has been von, 
the readership of 73 Magazine 
and this column* who have laken 
me through good limes and bad. 
It is through you. and with your 
help, thai I am able to maintain 
ihe breadlh of material in RTTY 
Loop, covering everything from 
sreasv old Model 15s to the laF 
est Windows 95-based digital pro- 
grams. Those of you who have 
been reading these pages for a 
while know that it was in this col- 
umn that many of you first saw 
the Epson MX-80 printer, one of 
the first dot matrix printers to hit 
the consumer market, as well as 
tales Of 6800, 6502, and 6809 
microprocessors back in the 
eight-bit days. 

Well, wilh that bil of nostalgia, 
let's see what readers of mid-1997 
are discussing, Paul Cecil 
KA5FPT/DA2PC, in Kaisers- 
lautcrn. Germany, the largest US 
military community outside the 
United States, offers his comment 
about the Pakratt program. He 
says that he, too, has the PK- 
232MBX and Pakratt II 55, wilh 
PACTOR. B liu looking over every- 
thing, he realized thai, "It is actu- 
ally calling up a separate program. 
All that the 5,5 upgrade did was lo 
add PACTOR to ihe menu, among 
some other things. 1 hope that this 
answers some questions." 

Thanks. Paul. I receive a vari- 
ety of questions on the various 
programs, and its always good to 
hear one ham's experience. 

With a problem solved, corner 
a problem presented. Doug 
VE61T passes along this problem: 

"I inherited a DR51 HF modem 
and ihe VHF packet adapter. 
However, no documentation 

74 73 Amateur Radio Today -July 



came with either unit. I was won- 
dering if you knew anything about 
these units, including connections 
and software I could use lo put 
them in service. 1 regularly read 
your articles and find them great/' 

Doug. 1 have less than you— at 
least you have the unit! Will pass 
it along, though, as you never 
know what someone might have 
in a basement drawer. 

After those two meaningful let- 
ters, here's a lighter note, from 
Robert E. Pearson W9KKL. who 
flatters me wilh the following: 

"J li si a short note: I think I have 
read every word you have writ- 
ten in 73 Magazine. 1 used to bor- 
row a friend of mine's 73 from 
about 1973 lo about 1976. They 
lowered the price about that lime, 
and I started taking il, and have 
ever since. Back then 1 was really 
broke. Although 1 myself do not 
play RTTY now, I used lo. The 
Internet sort of takes mv time. I 

m 

have a PK-232, HAL CT-2200, 
and an old Model 19. 

*i really like your home page, 
the greeting, and everything. 1 
have one comment, please add 
your picture and perhaps your rig 
to your home page." 

With space on my server at a 
premium, 1 am sure that my fans 
would rather have a RTTY pro- 
gram to download than sec my 
punim, but Til give it some 
thought. That greeting Bob refers 
to, by the way. is a little clip of 
my voice welcoming you to ihe 
page. Check the address of the 
RTTY Loop Home Page below, 
and if you ve not checked it out 
recently, have a look. Thanks for 
the strokes, Bob, and I'll try to 
live up Lo it all! 

Last month I detailed some of 
the problems faced b> amateurs 
using AEA equipment, pending 
the restoration of commercial 
support, S. Neil Xenias N4CTB 
passes along the following bit of 
wisdom: 

"I really enjoyed your column 
in the March issue. I, loo, am sad- 
dened by whai happened to AEA 
(you can guess which mullimode 
controller 1 own?). 1 wanted to 

1997 



offer some help to your readers 
which may or may not be fruit- 
fiiL Here in Virginia, many of the 
Army MARS members use the 
PACTOR mode to handle MARS 
traffic, A large percentage of these 
folks use the AEA PK-232. 

"The MARS group here has a 
Technical Librarian* who main- 
tains copies of technical manuals, 
equipment conversion info, and 
most recently, EPROM lisiings. If 
your readers) in need can hook 
up wilh a local MARS member 
in their town, chances are that 
they can gel a sei of EPROMS 
burned for them. 'Course, they'll 
probably gel the recruitment 
pitch, but wc need all the 
members wc can get — Ml! 

As a former member of a 
MARS program, quite active dur- 
ing ihe 1970s* 1 can vouch for the 
thoroughness of the system. For 
those not familiar with the Mili- 
tary Affiliate Radio System, this 
is a volunteer civilian organiza- 
tion which acis to support mem- 
bers of the armed forces 
throughout the world. During the 
Vietnam war, ioi example, 1 spent 
many nights and weekends han- 
dling message traffic between 
soldiers in the field and their 
families at home. So, if they can 
help you h don't be shy about look- 
ing into helping them. They can 
use you, and you'll feel good for 
doing it. 

On the RTTY Loop Home 
Page, I have a program called 
A2FTerm, m Apple 11 RTTY pro- 
gram, with a request for com- 
ments, Since I gel a fair number 
of requests for Apple RTTY pro- 
grams, let me pass along what 
Paul N5YFK has to say about it: 

"U is a workable Apple 11 pro- 
gram — in faci, considering ihe 
old 6502 computer chip and the 
instruction set* a very good pro- 
gram. ( I started off programming 
in 6502 machine language for the 
Apple IL) A very nice feature is 
thai it wilt run on a system with a 
single disk drive, It can be down- 
loaded to a PC, and then trans- 
ferred over lo an Apple wilh some 
ease If each computer (PC & 
Apple) has a modem, all you have 
lo do is conned litem with a 
phone cord, have one on standby 
< i.e., ATA in Haw** lingui and just 
dial a single digit with the other. 
The one on standby will pick up 



the phone and you have commu- 
nication between the two. Down- 
load the file from the PC to ihe 
Apple and save to disk. Thai's all 
If you don't have them both at the 
same location, a local phone cull 
will do. 

"The only real problem with 
some Apple files is lhat they are 
compressed, and just plain unus- 
able unless you have a big Apple 
system with a hard drive and thai 
particular version (often obsolete, 
abandoned, and nowhere to be 
found i of the compression pro* 
gram. So support the Apple IL but 
in uncompressed programs — af- 
ter all. they really are small by 
today's standards. 

"I appreciate the program — as 
1 have still have 3 working 
Apples, one of which I lend oui 
to persons wanting to try packet 
alon* with an older MFJ TNC** 

Thanks, Paul, for that look at 
an older, but still quite usable, 
program, I know that ihere are 
those who would like this pro- 
gram, which is on Disk #7 of the 
RTTY Loop Disk Collection, al- 
beit on a PC- formatted disk. 

From an older program to a 
newer one, Stan Hunlting 
KF0IA, passes along the follow- 
ing notice about a program for 
Kamronies TNCs; 

%t As a computer-literate ama- 
teur radio operator, there's an ex- 
cellent chance you're active on 
one or more of the 'digital' 
modes, and that you use 
Kantronics TNCs in that activity, 
Also, as an Internet-connected 
amateur radio operator, there's an 
equally good chance you use MS 
Windows and a fast computer. If 
so T you should know ahout 
KaWin — the performance-en- 
hancing soli ware designed espe- 
cially for Kanironics TNCs and 
MS Windows. Visit the KaV^ 
home page, at [http://www 
.mutadv,com/kawin| (Keyword 
to.) lo learn more and lo down 
load the full KaVVin system to try 
it on your own system. 

"KaWin supports all T\( ' com- 
munication modes, including 
VHF and HF packet radio; CW. 
RTTY 7 . ASCII and Navtcx: Amior, 
PACTOR. G-Tor, Tor-standby 
and G-Tor Monitor. Its Host mode 
interface means KaWtn and your 
TNCs communicate compuicr-lo- 
computer wilh full use of your 



Hsk Krboom 



Number 75 on your Feedback card 



Michael J, GeierKBIUM 
c/o 73 Magazine 
70 Route 202 North 
Peterborough NH 03458 



More video recording 

For the past several months, 
we've been exploring television: 
its history* signals and manipula- 
tion. 1 realize the topic of video 
recording isn't strictly ham-ori- 
ented, but video is, more and 
more, a part of the radio experi- 
ence, and an understanding of it 
can only enhance your ham radio 
fun. especially if you're interested 
mSSTVorATV. 

Last month, we took a look at 
the first practical video recorder, 
the quadruple \ VTR, designed for 
broadcast use. if you* ve ever been 
in the control room of a TV sta- 
tion, you've probably seen one of 
those behemoths. The high- 
piiched whine the headwheel 
makes is not easily forgotten! 
Quad VTRs were incredibly com- 
plicated, and, as 1 mentioned last 
time, never filtered down to the 
home-use level. 

A home video recorder was the 
''holy grail" of the electronics in- 
dustry for a good twenty years, 
Anyone with some foresight 
knew such a product would be a 
smash hit, perhaps as big as tele- 
vision itself, and everyone wanted 
to be lead dog in that race — so 
why did it take so long to finally 
happen? 



Your Tech Answer Man 

Not easy 

As we explored last time, there 
were many obstacles to recording 
a video signal, at any price level. 
And certainly, no home user could 
afford a tape recorder that cost 
more than his house* Was there 
any way to make an affordable 
home video recorder? Until about 
1970. the answer seemed to be 
"no." Many companies tried all 
kinds of ways to bring the cost of 
video recording down, giving up, 
one by one, as they encountered 
technical hurdles that couldn't be 
solved at the price levels neces- 
sary for home use. RCA was a 
pioneer in this area, and spent 
millions of dollars researching the 
HVTR," as they called it. Yet, 
the company finally announced, 
around 1972, as I recall, that "it 
just can't be done," and aban- 
doned the project. Of course, it 
was done, slowly but surely. 
Here's how: 

A different beast 

In the early 1960s, Sony, 
Matsushita (Panasonic), Toshiba 
and other Japanese companies 
had begun to introduce non- 
broadcast-quality machines in 
the $2,000 range. At first, they 
were black-and-white only, as no 
one had yet solved the timing 
problems required for color re- 
cording. These machines used the 
"helical scan" principle. Like 



dual-port TNCs and simultaneous 
multiple I~\Cn. multiple ports, mul- 
tiple streams and multiple radios. 

^KaWTn is a native MS Windows 
program with a no-compromise 
design for 486 and Pentium sys- 
tems. Looks 1 ike, feels like and talks 
to your other Windows applications 
with fully event-driven communi- 
cations. Intuitive menus, full mouse 
support and on-line help make 
KaWin is easy to learn. Qu ick key s. 
Quick connects. Brag files. CQ ro- 
bot, restartable binary file transfers, 
ANSI graphics and much more," 

This is a nice program, which 
can be downloaded in a "try 



before you buy" arrangement. 
Thanks to Stan for passing along 
the information. 

Check out the RTTY Loop 
Home Page for all that 1 mentioned 
above* and more stuff as well, at 
[http://www2.ari.net/ajrAtty/J. Let 
me hear from you by snailmail at 
the post office box address above, 
or by E-mail at [ajr@ari.net], 
on America Online at [Marc 
WA3AJR]. or on CompuServe via 
the new address, [Leavey@ 
compuserve.com]. Next month, 
more on new RTTY programs, old 
RTTY pictures, and crazy RTTY 
users. 



quad machines, they had spin- 
ning heads and employed FM 
recording. But that's where the 
similarity pretty much ended. 

Quad machines used a very 
high head-to-tape speed of 1.500 
inches per second, recorded on 
two-inch-wide tape, and laid 
down tracks which were nearly 
perpendicular to the tape travel. 
That resulted in a short track (no 
longer than the width of the tape), 
so it took several head sweeps to 
make one TV field. That required 
very tight servo control of the 
headwheel, so that the signal dis- 
ruptions, inevitable as one head 
left the tape and the next one 
made contact, occurred in por- 
tions of the signal which were not 
visible on the screen? Even worse, 
the long-lasting but brittle ferrite 
material that would give long ser- 
vice life could not be used for the 
heads, because the sideways mo- 
tion of the tape against the heads 
wouJd break it — so quad heads 
wore out fast. 

The helical concept, so named 
because the diagonal wrap of the 
tape around the head drum looks 
like a helix (if it wraps all the way 
around, which modern machines 
don't), had been tried by Ampex 
but discarded as unsuitable for 
broadcast use. For less critical 
applications, though, it had tre- 
mendous advantages, along with 
a few disadvantages, The diago- 
nal wrap resulted in long, diago- 
nal tracks on the tape, whose 
length was limited only by the 
circumference of the drum, rather 
than the tape width. Conse- 
quently, narrower tapes could be 
used, and one-inch, three-quarter- 
inch and one-half- inch machines 
were common. Plus, those long 
tracks meant that an entire TV 
field could be recorded in one 
head sweep, vastly simplifying 
the servo required to control the 
head motor, and easily keeping 
the signal disruption (called the 
"head switching point") out of the 
picture, near the vertical sync. 
Another great benefit was that, 
since the tape direction and direc- 
tion of the head scan were at a 
fairly close angle, there was very 
little sideways stress on the heads, 
so Temte could be used. Coupled 
with advances in tape manufac- 
ture that made for much smoother 
tapes, and a slower scanning 



speed (because broadcast-quality 
bandwidth wasn't needed), 
headwear was finally reasonable, 
even though the scanning speed 
was still over 300 inches per sec- 
ond. Now. expensive video heads 
could last for thousands of hours, 
rather than hundreds. 

This sounds like such a great 
system — why couldn't the broad- 
cast machines use it? Unfortu- 
nately, it had some serious 
disadvantages as well. The first 
was thai, in order to wrap the tape 
diagonally, it had to be pulled out 
of its normal plane of motion- You 
could do that but it required some 
cone-shaped guides, and the tape 
motion wasn't terribly stable. 
Plus, the much larger mass of lhe 
head drum meant you couldn't 
servo-control it very fast, so ul- 
tra-tight edit timing, so necessary 
in the broadcast world, wasn't 
possible. But perhaps the biggest 
disadvantage to helical scanning 
was its generally poor time base 
stability. In other words, the tim- 
ing of the signal wobbled too 
much for broadcast use. By law, 
broadcasters must meet some 
very strict signal standards, and 
no helical machine could even 
approach them. Wobbly timing 
means wobbly pictures, and that 
just wasn't tolerable in a TV 
station. 

In non-broadcast applications, 
though, some timebase error 
could easily be tolerated. Helical 
machines were quickly accepted 
in educational and corporate mar- 
kets. Institutions and businesses 
could afford to spend a few thou- 
sand dollars on TV equipment, 
and that market opened the gate 
for development of the home 
video recorder. The race was on! 

More obstacles 

So, if machines could be made 
to sell for $2,000, why not just 
make lots of them, so that the 
economy of mass production 
would bring the cost down? Af- 
ter all. we see that today in many 
initially expensive products, like 
computers. Alas, video recorders 
are fundamentally different from 
most other high-tech products: 
they're intensely mechanical, 
rather than mostly electronic. It's 
easy to mass-produce circuit 
boards, but not highly precise 
mechanical assemblies. Video 



73 Amateur Radio Today ■ July 1997 75 



Crrr's corner 



Number TS on your Feedback c^rtf 



Joseph J. Carr K4IPV 

P.O. Box 1099 

Falls Church VA 22041 -0099 

[carrjj@aol.com] 

Safety first: some antenna 
erection guidelines 

One reader once wrote and 
took me lo task for spying loo 
much about safety. He claimed 
thai interest in safely is minimal, 
and that everything regarding 
S&feQ is (his words) "intuitively 
obvious to even brain-dead idi- 
ots." 1 most respectfully disagree. 
Safety is not a "given," especially 
where antennas are concerned. 

Antennas arc inherently 
dangerous to creel it" certain 






heads had to he positioned on the 
drum by hand, under a micro- 
scope, to a tolerance of a couple 
of microns, in all ihrcc dimen- 
sions — and the roundness of the 
drum itself had to be within about 
five microns, or interchange of 
tapes between machines would be 
unusable. Also. b> the time seri- 
ous development was underway, 
there was one very tricky require- 
ment that industry was willing to 
do without but home users never 
would: color. Although the tech- 
nical issue had been solved by the 
early 1970s, and color machines 
were available to industry, the 
cost of color recording was still 
too high for home use. Worst of 
all, the industrial machines still 
consumed too much tape per hour 
of programming, and manufactur- 
ing videotape wasn't cheap. 

Although today we take S2 vid- 
eocassettes for granted* it wasn't 
always like that! Not so long ago. 
those same tapes were SIM. Reel- 
to-reel videotape cost about $25 
per hour in the 1970s, and that 
was when money was worth 
much more. The cost per hour of 
tape was, perhaps, ihe biggest 
obstacle of them all. 

Here it comes 



In an effort to reduce tape con- 
sumption, various schemes were I 
tried. One thai actually appeared 
in some industrial machines was 
to record only every other field | 

76 73 Amateur Radio Today • July 



precautions are not followed, It's 
impossible to foresee all the situ- 
ations that you might face In 
erecting an antenna. 1 would like 
to give you all possible warnings, 
but that isn't possible. You're on 
your own, and must take your 
own responsibility when install- 
ing an antenna, I can* however, 
give you some general safety 
guidelines. Knowledge of what 
you face* some hard-nosed sound 
judgment, modulated by common 
sense* are the best tools on any 
antenna job. 

One rule that is an absolute is 
that no antenna should ever be 
erected where the antenna, the 
feed line or any part thereof 



ol the TV signal, and play the 
same field back twice. Called 
"skip field" recording, it reduced 
tape consumption by 50 f r * but it 
resulted in a loss of vertical de- 
tail of the picture by the same 
amount. Worse, it often caused 
jumpy, jittery pictures. Sony's 
CV-2000 and other mid-1960s 
machines used the technique, but 
it ww no real solution. 

Eventually, a Japanese standard 
called HI AJ (Electronics Industry 
Association of Japan) was agreed 
upon. Phis formal used half-inch 
tape at seven and a half inches per 
second, and recorded all the 
fields. Tapes made on an EIAJ 
machine could be played on any 
other, regardless of manufacturer. 
EIAJ units were very' p°F u l ar m 
universities and early cable TV 
channels. Eventually, an EIAJ 2 
format was created for color re- 
cording, but it was soon eclipsed 
by a great advance in helical tech- 
rtologv which drasticallv reduced 
tape consumption, thereby begin- 
ning the onslaught of the home 
video formats. At last* true home 
v ideo recording was coming. 

Next lime, we'll explore the 
modem VCR: how it came to be, 
how it works, the sweeping effect 
its creation has had on the manu- 
iaeturing and development of 
other products, and why it's so 
cheap today. The grail is just 
around the comer,. 

Until next month, 73 de 
KB1UM, 

1 997 



crosses over a power line. EVER ! 
This is a **no kidder" — don't do 
it! Power lines look insulated, but 
there are often small breaks or 
weakened spots (especially a 
couple days or more after instal- 
lation) that can bring the antenna 
into contact — lethal contact — 
with the hot power line. Every 
year or so we hear about an S WL, 
scanner/monitor but! ur ham ra- 
dio operator being killed by toss- 
ing an antenna wire over a power 
line. Avoid making yourself into 
a high power resistor ! 

The same rule applies to situa- 
tions where the antenna can fall 
onto a pow er line if it falls down 
or breaks. You have to examine 
the situation with a critical eye to 
see if there is any possible way 
for that antenna, or its support 
structure, to fall onto a power line 
if it breaks in any way whatso- 
ever, On my lot in Virginia I have 
a 23-foot mast erected on the back 
of the house, When I installed it I 
made a scale drawing of the back 
yard showing the path of the 
power line. The 23-foot fall radius 
of the antenna w as plotted for sev- 
eral possible antenna locations. It 
should not intersect either the 
power lines or the cable TV line 
when it falls. It should also not 
be in a position to fall over a pe- 
destrian path* a place where chil- 
dren play, or across a public 
walkway or street (lawsuits arc 
messy). Or as one chap found out 
the hard way, it should not be in a 
position to fall through a window! 

Another caution is that you 
should be physically fit to do the 
work. While the on-the-ground 
portion of the work is not usual I y 
loo strenuous, any climbing at all. 
even on ladders, can be taxing for 
some people. Antenna materials 
are deceptively lightweight on the 
ground, but when you get up on 
even a small ladder, they are re- 
markably difficult to handle. At- 
tempting to manhandle a 22- foot 
\erlical once wiped my back out, 
and I consider myself fortunate 
thai the pain hit me after Yd dis- 
mounted the ladder. Besides, if 
you could see me, you would 
wonder why a man my size w r as 
on any ladder in the first place. 
Before using a ladder, learn how 
to use a ladder, A lot of 
homeowners, whether putting up 
antennas or painting the upstairs 



windows, fall off ladders thai 
were being used incorrectly. 

If the w ind blows even a few 
miles per hour, the danger is mag- 
nified considerably. I recall a 
friend — who is a large, strong 
bear of a man — attempting to in- 
stall a 26-elemenl television "all 
channel" antenna on the roof of 
his two-story house. The antenna 
was easily handled with one hand 
on the ground and with no wind 
blowing, but up on the roof it was 
a different story. He was on the 
peak of the roof, when a gust of 
wind came up suddenly and 
caught the antenna It acted like a 
hang gl ider, and pulled him off the 
roof, plunging down two stories 
to the patio below; he fractured 
his pelvis and busted a leg. Ex- 
pensive TV antenna* I reckon. Be 
ca refill. 

One good rule is to always 
work under the buddy system. 
Ask as many friends as are needed 
to do the job safely, and always 
have at least one assistant even 
when you think you can do it 
alone. Erecting a large antenna — 
and some small ones — without 
help is just plain stupid. At least 
have someone around who can 
call 9 1 1 if you mess up. 

Always use quality materials 
and use good work practices. An- 
tennas, being potentially danger- 
ous, should always have the best 
of both goods and workmanship 
in order to keep quality high. It is 
not just the electrical or radio re- 
ception workings that are impor- 
tant, but also the ability to stay up 
in the air and safe. 

When planning the antenna 
job, keep in mind that pedestrian 
traffic in your yard could possi- 
bly affect the antenna system. 
Wires are difficult to see T and if 
an antenna wire is low enough to 
intersect with someone's body, 
then it is possible to cause seri- 
ous injury to passersby. Saboteurs 
and the Resistance used to knock 
Nazi motorcyclists off their bikes 
(and to their doom) using a bit of 
wire stretched across the road. 
Even when the person is a ires- 
passer, the courts may hold you 
liable for injuries caused by an 
inappropriately designed and in- 
stalled antenna. Take care for 
safety, not only for yourself, but 
for others. 

One necessary reminder is that 



your local government might 
have some interesting ideas — le- 
gal requirements actually— con- 
cerning your antenna installation. 
The electrical, mechanical and 
zoning codes must be observed. 
There is a great deal of similarity 
between local codes because most 
of them are adaptations from cer~ 
tain national standards. But there 
arc enough differences thai one 
needs to consult local authorities. 
Indeed, you may need a license 
or building permit to install the 
antenna in the first place. 

One problem that SWLs and 
scanner monitors face is that their 
antennas are not protected by the 
FCC as are ham antennas (local 
governments have limited rights 
to regulate ham antennas; only 
"reasonable" mechanical and 
electrical standards can be im- 
posed), so it may be illegal for you 
to install any antenna, About 30 
years ago a friend of mine in a 
radio dub found out that his 
county had an ordinance that said 
an outdoor antenna must be 
double its own height plus fifty 
feet from the nearest property 
line. He received a summons af- 
ter a complaint from a neighbor. 
In a county full of quarter-acre 
borne lots, however, that was a 
ridiculous law. Very few outdoor 
TV antennas met that strict re- 
quirement! So Hal went to the 
court house and asked for 50,000 
complaint forms. Using a local 
county directory, he proceeded to 
file the same complaint as he'd 
received against every home- 
owner in the area, The county 
board repealed the law during the 
next meeting. 

Save all paperwork regarding 
your building permit, including 
inspection decals or papers, and 
the original drawings (with the 
local building inspector's 
stamps). If a casualty occurs, then 
your insurance company may 
elect not to pay off if you have 
violated an electrical, mechanical, 
building or zoning code. That 



clause may be overlooked by an 
enthusiastic antenna builder, but 
it could prove to be a costly over- 
sight. 

If you think this commonsense 
information is "too much** about 
antenna safety, then 1 will cer- 
tainly be praying for you. Please 
be careful... you people are my 
friends and I don't like to see 
friends get hurt. 

New books 

Over the years a number of 
readers have honored me by buy- 
ing my books, and for those sup- 
porters 1 am deeply grateful. 1 
have recently signed to do a line 
of several books called the Elec- 
tronic Circuits Guidebooks. The 
First one, which is on sensors and 
sensor interfacing, should be out 
about the time this article is pub- 
lished. The publisher is Howard 
W. Sams & Company /PROMPT 
Publishing (2647 Waterfront 
Parkway East Drive, Indianapo- 
lis IN 46214*2041), If you en- 
joyed the electronics books once 
published by the old Sams, and 
by TAB Books when they were 
still in Blue Ridge Summit PA, 
then you might want to check out 
the new Howard W, Sams cata- 
log, 

Those of you who have en- 
joyed my articles on radio and 
science may be interested in a 
new book F ve just signed for with 
Sams on RadioScience Observing 
(a term I coined for all forms of 
scientific observation using radio 
receivers, including whistler 
hunting, radio astronomy, Jovian 
radio signals, radio propagation, 
solar eclipse observations and so 
forth), I am just starting lo write 
it, so look for it early next year. 

If you have any ideas to share 
for the radioscience book, espe- 
cially if you teach science, then I 
would very much appreciate hear- 
ing from you. 1 also would enjoy 
receiving suggestions of any kind 
for this column. 



/ 



CornerBeam? 




SWR < \2z\ aCKrti the band 

Gain of a 15 fi Yagi 

No dimension ewer 7 ft 

■40 dB Front-To Back Rano 

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SPECittl EVENTS 

Continued from page 72 

refreshments. Free flyer by writing 
to The South Milwaukee ARC. Inc. 
RO. Box 102, South Milwaukee Wl 
53172-0102. Tel. (414} 762-3235, 
Tallin will be on 146,52 (WA9TXE) 
simplex as well as on many of the 
local repeaters, 

PETOSKEY, Ml The Straits Area 
ARC will host a Swap & Shop in the 
4-H Bldg. at the Emmet County 
Fairgrounds, Talk-in on 146.68(-) 
and 146.52. Contact Jim KC8FFS 
at (616) 537-2422 lor details, ForVE 
exam info, call Floyd KG8CS at 
(61$) 520-5503. 

JULY 12-13 

INDIANAPOLIS. IN The Indian- 
apolis Hamfest will host the ARRL 
Central Division Convention as well 
as feature a huge ham, computer. 
and electronics show. Marion 
County Fairgrounds, easy access 
from I-465 and I-74. Commercial 
exhibits, flea markets, forums, 
banquet, overnight camping 
available, home-brew contest, T- 
hunts, prizes, more. Write or call 
Indianapolis Hamfest Association, 
PO. Box 88677, Indianapolis IN 
46208; tet. (317) 251*4407; (www 
Jndyhamfest.com] 

JULY 13 

KIMBERTON, PA The Mid-Atlantic 
ARC win sponsor an indoor/outdoor 
hamfest at Kimberton Fire Company 
Fair Grounds, Rte. 113, south of the 
intersection with Rte. 23,, starting at 
7 a.m. Tables, 1-4, $10 ea.; 5 or 
more, $8 ea,, not Including ad- 
mission. Tailgating, $5, Adm. $5. 
Talk-in on 146.835(-) and 443.80+ 
PL 131.8. Contact Bob Haase 
W3SA T (610) 293-1919; FAX (610) 
293-7688; E-mail: [wb3joe@ 
vQicenetcom} t or write to MARC, 
P.O. Box 352, Viltanova PA 19085. 



PITTSBURGH, PA The North Hills 

ARC will hold their 12th annual 
hamfest 8 a.m.-3 p.m. at Northland 
Public Library. 300 Cumberland Rd, 
Talk-in and check-ins will be on 
14909 W3EXW. the North Hills ARC 
rptn Free admission, free parking. 
One free automobile-sized space 
per tailgater; each additional space 
$5. The hamfest is handicap/ 
wheelchair accessible. Contact Bob 
Ferrer Jr. N3DOK at (412) 367- 
2393; or via E-mail at (bferreyG 
nauticom.net] t or through the North 
Hilts ARC Web site at [http:// 
nharc.pgh.paus}. 

78 73 Amateur Radio Today • July 



SUGAR GROVE, IL The Fox River 
Radio League annual hamfest will 
be held at Waubonsee Community 
College, Rte. 47 at Harter Rd., 
Sugar Grove IL. Flea Market setup 
Sat. at 7 p.m., Sun. 6 a.m.-8 am 
Doors open Sun. at 8 a.rn. VE 
Exams 10 a.m. Bring original 
license, copy of license and photo 
ID. Talk-In on 147,21 0(+) {PL 103.5/ 
107.2). Contact Diana Skube 
WD9APL C/O FRRL, RO. Box 673, 
Batavta IL 60510. Tei (530) 293- 
7485. 

JULY 19 

NEWPORT NH Sugar River 
Amateur Radio Festival and Flea 
Market will be held on the Newport 
Common Saturday, 8 am-3 p.m. 
Food, tailgaters, special event 
station, ham radio demos, vendors, 
RC model helicopter demos, prizes, 
VE test session, flea market, more. 
Overnight camping Friday. Exit 8 off 
191 (12 mi. east) or Exit 12 off I89 (8 
mi, west) to Town Common in 
Newport. Taik-in on 146.76 rptr/ 
146,52 simplex. Adm. S6 tailgaters, 
$10 fleamarketers, buyers FREE. 
Pre-registration encouraged. 
Contact: Rob Boyd N1CIR, $48 Rl 
103, Sunapee NH 03782-3719: 
phone (603) 863-5383. Packet; 
N1CiR@WA1WOKNH. 

JULY 20 

AUGUSTA, NJ The Sussex County 
ARC'S 19th Annual Hamfest will 
be held at the Sussex County 
Fairgrounds, Plains Rd., beginning 
at 8 a.m. Reg. is $5 per person, YL 
and harmonics free. Limited indoor 
table space $13 per table; outdoor 
space $10 per vender. Talk-in on 
147.300 and 224.50 rptrs., and 
146.52 simplex. For advance sales 
and info, contact Daniel Carter 
N2ERH, 8 Carter Lane, Branchvttle 
N J 07826. let. (201) 948-6999. 

BRUNSWICK, MO SweatFest 97" 
will be held rain or shine by the Mid 
Atlantic DX and Repeater Assn., at 
the MARC Train Station, Seminars, 
flea market, demonstrations, 
commercial vendors, and an ARRL 
test session will be featured, 
Contact MADRA Sweatfest "97 r 230 
N; Potomac St., Suite #2B. Hag- 
erstown MD 21740. VE exams will 
begin promptly al 9 a.m. (be there 
at 8:30 a.m.). E-mail to [madraciub 
@ AOL.COM]. or [http;//members 
.aol.com/madraciub]. Talk- in on 
147.06 and 448.125. 

CAMBRIDGE, MA The MIT Elec- 
tronics Research Soc the MIT 
Radio Soc*, and the Harvard 

1997 



Wireless Club will hold a tailgate 
electronics, computer and amateur 
radio Flea Market Sun,. Juty 20th, 9 
a.m -2 p.m. at Albany and Main St., 
Cambridge MA. Admission $4. 
Sellers $10 per space at the gate. 
S9 in advance (includes 1 adm). 
Setup at 7 am. For space reser- 
vations and info, call ($17) 253- 
377$. Mail advance reservations 
before the 5th to W1GSL RO. Box 
397082 MIT BR, Cambridge MA 
02139-7082, Tallin on 146.52 and 
449.725/444.725, PL2AW1XM rptr 

VAN WERT OH The Van Wert ARC 
will hold their 10th annual hamfest 
at Van Wert County Fairgrounds, US 
127 south, 8 a.m. -3 p.m. Free 
parking. Overnight $10 Adm. 34. 
Pre-reg, for VE exams.; send SASE 
to Bob High KA8IAF, 12838 
Tomfinson Rd . Rockford OH 45882, 
or call (419) 795-5763. Tables $10 
(8 ft, J, For table reservations, send 
SASE to VWARC P.O. Box 602. 
Van Wert OH 4589 1 -0602. TeL after 
5 p.m., Bob WD8LPY. (419)238- 
1877, E-mail to [bamesrl® bright 
.net] or [http://www.bright.net/ 
~bame$ri/w8fy>htm]. Talk-in on 
146,850/,250. 

JULY 25 & 26 

OKLAHOMA CITY, OK The Central 
Oklahoma Radio Amateurs will 
sponsor their 24th annual "Ham 
Holidays 97" at the Oklahoma State 
Fair Park (Hobbies, Arts & Crafts 
Bldg,)> northeast of the 1-40 and I- 
44 intersection, Doors open 5a,m - 
8 p,m. Fri. r July 25th and 8 a.m. -5 
p.m, SaL, July 26th. Technical and 
non-technical programs, fox hunt, 
VE exams and flea market. Pre-reg. 
$7 r $9 at the door Flea market 
tables are 310 ea. in advance, $15 
ea. at the door (if available). Talk-in 
on 146.82. Additional info and reg. 
forms are available on the CORA 
Web site at [www.geocities.com/ 
heartfand/7332]. Address other 
inquines to Ham Holidays '97, P.O. 
95942, Oklahoma City OK 73143; 
or E-mail [MfpnWswbellnetl 

JULY 26 

NEAR WAYNESVILLE. NC The 
Western Carolina ARS of Asheville 
NC will hold its 22nd annual hamfest 
8 am. -4 p,m. at the Haywood 
County (NC) Fairgrounds. Exit 24 off 
Interstate 40, then south on Hwy 
209 3 mi. New and used radio gear, 
flea market tailgating. Adm. $4 
advance, $5 at the gate. Free 
parking. VE exams at 2 p.m. For 
info, contact Norman Harrili N4NH 
at (704) 253-1192. For deafer and 
flea market info, contact Dan 



Henderson N1ND at (704) 684- 
6339. For tickets* contact Bob 
Helton KS4FX. P.O. Box 1488, 
Asheville NC 28802, For general 
into, call Tommy Queen K48NP, 
(704) 258-2639. Talk-in on 146.91/ 
.76. 

JULY 27 

BALTIMORE, MD The Baltimore 

Radio Amateur Television Soc. will 
sponsor the Maryland Hamfest 3^n6 
Computer Fest at the Timonium 
Fairgrounds. York Rd. off 1495, I* 
83. Accessible to the handicapped. 
Kids under 12 admitted free, adults 
$5. Tailgating spaces 37 each, first- 
come, first served. Check in for free 
VE exams at 8:30 a.m.. pre-reg. 
required: call John Creek WB3GXW 
after 6 p.m. at (301) 572-5124. For 
info and table reservations, write 
BRATS/P.O, Box 5915, Baltimore 
MD 21282. Tei. (410) 467-4634 
voice or FAX. Web site [http:// 
www.smart.net/-brats] or E-maif 
[brats@amart.net], 

RACINE, W) The Racine Mega- 
cycle Club will sponsor its annual 
Swapfest on Sun,. July 27th, at the 
South Hills Country Club on the I- 
94 east frontage road between Hwy. 
20 and Cty. Rd. K. Dealer setup at 
6 a.m. Public access 8 a.m -2 p.m. 
Talk-in on 147.87/.27. Indoor air- 
conditioned space at $8 per table. 
Tailgate space is available, Adm, $5 
at the door, $4 plus SASE advance 
to Racine Megacycle Club, RO. Box 
3, Racine Wl 53401. Forums h 
dealers, exhibits, demos, VE exams. 
Contact Dave Voss WB9USI, (414) 
554-7565 

AUG 2 

HOUGHTON, Ml The 1997 Up- 
per Peninsular Amateur Radio 
Convention, better known as the 
U,P Hamfest, will be held at the City 
of Houghton's Dee Stadium facility, 
located on the downtown waterfront. 
Doors open to the public at 9 a.m. 
EDT. Vendors and persons selling 
equipment will have main floor 
access beginning at 7 a.m. EDT 
Friday eve. access will also be 
available, although overnight 
storage will be at owners" risk. AC 
power by previous arrangement 
only. Tables are 36/full table. $4/hait 
table. Contact Roland Burgan 
KB8XI, (906) 482-2403; E-matt 
[rburgan©up.net] t Packet: [KB8XI 
@W8YY.#UPMt.Mt.US.NA], For 
fodging/camping/boa ting info , 
contact Keweenaw Chamber of 
Commerce at 1-800-338*7982, or 
on the Web at [http://www.portup 
, com/mainstr/chamber/home.h tmf]. 



AUG2&3 

JACKSONVILLE, FL The 1997 
ARRL Matronal Convention will be 
held at the Osborn Convention 
Center in Jacksonville. Open to the 
public Sat. 9 a.m -5 p.m.; Sun. 9 
a.m.-3 p.m. The Greater Jack- 
sonville Amateur Radio & Computer 
Show will host the event. Free 
parking in the main convention 
center parking lot. Setup 1 p.m.-6 
p.m. Fri., Aug, 1st. Upgrade VE 
exams will be offered at 9 a.m. on 
Sun. at the convention site. A wide 
variety of programs and forums will 
be presented by ARRL staff and 
noted authorities of national stature. 
Banquet at 7 p.m. Sat. at the HQ 
hotel, the Jacksonville OMNI, A 
special rate of $69 per night is 
available to those mentioning the 
convention. Phone (904) 355-6664 
or 1-800-843-6664 for reservations. 
Reg. for the entire weekend is only 
$8 t which includes parking in the 
main lot. For more info, visit the Web 
site at {http://users.southeasi.net/ 
-jnrtQQrQ/hamfest.htmi], or write 
Greater Jacksonville Hamfest Assn., 
PO. Box 27033, Jacksonville FL 
32205. For swap table reservations, 
contact Karl Hassier N4DHG, 2767 
Scott Circle, Jackson vi fie FL 32223 \ 
or phone (904) 268-2302. Tables 
are $25 ea. for the weekend. For 
commercial exhibitor space, contact 
Vern Ferris KB4 VPU, 356 Aries Dr f 
Orange Park FL 32073. Tel (904) 
272-7250, 

AUG 3 

MARSHFIELD, Wl The Marshfiefd 
Area ARS wiil host their 6th annual 
Potluck Picnic and Swapfest at 
Wildwood Park, Marshfield Wl f 
starting around 11 a.m. All are 
welcome. Talk-in on 147.180, 
Contact Guy A. Boucher KF9XX, 
107 West Third St., Marshfield Wi 
54449^ Tel. (715) 384-4323. 
Packet: [KF9XX@W9IHW.Wt 
.USA.NA]. E-mail: [guyboucher 
@tznet.com], 

PEOTONE, IL The 63rd Annual 
Hamf esters Hamfest will be held 6 
a.m. -3 p.m, at the Will County 
Fairgrounds (I -57 exit 327 East) in 
Peotone. Sat setup 3 pm-11 p.m. 
Free overnight parking. Secured 
building. Main exhibition hall opens 
at 8 a.m. Flea Market electric 
hookup fee is $10, Electricity will 
cost $10 for 4 tables or less* 
electricity is free for more than 4 
tables. One free ticket per vendor, 
all others, $4 in advance, $5 at the 
gate. For reservations, etc., contact 
Dave BraseiNFQN, 8933 W. 110th 
St., Worth IL 60482, 



AUG 9 

BARABOO, Wl The 1st annual 
Circus City Swapfest will be held at 
the Sauk County Fairgrounds 7 
a.m.-noon, rain or shine. Tailgate 
sales. Free parking. Admission $5 
at the gate! $4 in advance. Tables 
$5 for 8 ft. (includes one admission) 
Electr. available. For advance 
tickets and tables, contact Yellow 
Thunder ARC, 1120 City View Rd. t 
Baraboo Wl 53913. Check the Web 
site at [http://wwwJheforax.com/ 
-sschulze/hamfest.htm]. 

AUG 16 

ROANOKE, VA A hamfest/ 
Computer Show will be held by the 
Roanoke Valley ARC, SaL, Aug. 
16th, 9 a.m.-5 p.m. at the Exhibit 
Hall, Roanoke Civic Center, 
Roanoke VA. Setup at 6 a.m. with 
help available. Features include 
equip, dealers, free forums, two 
walk-in VEC exam sessions, and an 
indoor/outdoor flea market. Adm. is 
85 at the door or in advance, 
outdoor tailgating $5, Indoor flea 
market tables S10 per table, dealer 
tables $20 ea. (plus S20 for electr.). 
Make checks payable to r and mail 
an SASE to RVARC f P.O. Box 2002, 
Roanoke VA 24009. Dealers and 
inside flea market contact Claude 
KE4UVO, (540) 774-8971 f or 
[ke4uvo@intriink.com}. All others 
contact Terry AE4EW, (540) 890- 
6762 or [ae4ew@ixMetcom.com]. 
Talk-in on 146.985(-), 

SPECIAL EVENT STATIONS 

JULY 3, 4, & 5 

NEAR ROSWELL, NM An Amateur 
Radio Special Event Station will 
operate 1700 UTC-2400 UTC, 
daily, July 3rd P 4th, and 5th, to 
celebrate the 50th anniversary of 
the "Crash at Corona 11 near Roswell 
NM. Freq.: Approximately 20kHz up 
from the bottom edge of the General 
HF band edge, 6-40 meters (phone 
and SSB) r and in the Novice/ 
Technician (CW) HF section of 15 
and 40 meters. Listen for WSBI, 
WB5LYJ, NA5N and WA5WHN, The 
station will operate overlooking one 
of the debris fields near Corona NM. 
SWL reports are encouraged too. 
SASE required. Send a 9" x 12" 
SASE and 2 units of US first class 
postage, along with your QSL card 
to Jay Miller WA5WHN, P.O. Box 
6552, Albuquerque NM 87197-6552 
USA. Check the W5BI Wehpage for 
further developments, [http:// 
www.flash.net/~w5bi/], or contact 
via the Internet, [wa5whn@juno 
.com]. 



JULY 7-13 

AUSTIN, TX Amateur radio 
operators affiliated with the 
American Assn. for Nude Re- 
creation, the Naturist Soc, and 
the Federation of Canadian 
Naturists, will observe the 22nd 
annual North American Nude 
Awareness Celebration during the 
week of July 7th-13th. Special event 
stations will operate from naturist 
resorts throughout North America on 
the following frequencies: 7.265, 14.265, 
21.365 and 28.465 ± QRM, For a 
personalized certificate, please send 
QSL and 9" x 12" SASE to Bob 
Redoutey N5KF, P.O. Box 200812, 
Austin TX 78720-0812 USA. 

JULY 11-12 

PORTAGE DES SIOUX T MO The 

St. Charles County ARES will 
operate KG0YJ, 2300Z July 11th- 
1700Z July 12th, during their annual 
field activation. Freq.: 3.870, 7.270, 
14.270 and 28.370MHz. For a 
certificate, send QSL and a 9" x 12" 
QSL and SASE to Bill Bird KG0YJ, 
144 Ridgecrest Dr, ? Chesterfield MO 
63017-2653 USA. 

JULY 19 

SISTERVILLE, WV Tyler County 
Amateur Radio Organization will 
operate KC8GX! to commemorate 
the last working stemwheel ferry on 
the Ohio River. Operation will be 
1400Z-2200Z. Freq.: 3.860, 7.230, 
14.260, and 28.360. For a cer- 
tificate, send QSL and a 9" x 12" 
SASE to TCARO, P.O. Box 287 r 
Middlebourne WV 26149 USA. 

JULY 19 & 20 

STRATFORD, NY The Fulton 
County Dr. Mahlon Loomis Com- 
mittee will operate W2ZZJ on July 
19th and 20th to commemorate the 



171st anniversary of the birth of Dr. 
Loomis, the American radio pioneer, 
who was born at Oppenheim NY on 
July 21st, 1826, Operation will be 
from 1300Z-20Q0Zon the General- 
class phone portion of 75 r 40 and 
20 meters, and on the Novice 10- 
meter phone band. Also, on area 2- 
meter FM rptrs. For a parchment 
certificate and extensive literature, 
send QSL, contact number, and a 
#10 SASE (55 cents} to W2ZZJ, 
5738 ST HWY 29A, Stratford NY 
13470 USA. 

JULY 20 

TOTTENHAM, ONTARIO, CAN- 
ADA Members of the Central 
Ontario ARC will operate the 'Radio 
On The Train" event for the 4th year 
in succession, 10 a.m.^4:30 p.m,, 
EST (1400-2030 hours UTC). They 
will invite check-ins under the 
callsign VE3ZVT (the South Simcoe 
Railway Amateurs Station), and will 
be on 75 and 20 meters— frequency 
dependent upon current con- 
ditions—for HF f and for local traffic 
via rptr on 146,835(-) MHz, with 
103.5 transmit subaudible tone. 
Operators checking in with the train 
can receive a memento QSL card 
of the event upon request. Club 
members operate from the caboose 
of the steam train at hourly intervals 
from Tottenham to Beeton. 

JULY 27 

NEWINGTON, CT The Meriden 
ARC, W1NRG, will operate CW and 
phone, from the W1AW station, 
1400-1930 UTC, to celebrate its 
50th Anniversary. Operation will be 
on the General portion of the 10-, 
15- r and 20-meter bands and the 
Novice 10-meter subband. For a 
certificate, send QSL and a 9" x 12" 
SASE to Meriden Amateur Radio 
Club, R O. Box 583, Meriden 
06450 USA. 




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73 Amateur Radio Today • July 1997 79 



On the Go 



Number 80 on your Feedback card 



Mobile, Portable and Emergency Operation 



Steve Nowak KE8YN/5 
15475 Summerwood Avenue 
Baton Rouge LA 70817 



Effective communications 

One of the most fascinating 
aspects of amateur radio is its va- 
riety, There is literally something 
for everybody, from traditional 
Morse code to satellite eommu- 



aspects as rag-chewing, networks, 
public service or disaster commu- 
nications. iVIany new members of 
the ham radio commit n it v stall 
off on two meters, and local com- 
munications is among their first 
encounters with the hobby. 

Now most of us are a mixture 
of these two aspects of the hobby, 
enjoying both the technology and 



The ham community is just that — a 
group of people with a common 

interest " 



nications, from experimentation 
to chasing DX, This diversity, 
naturally, attracts different people 
for different reasons, leading to a 
wide variety of operating styles, 
techniques and attitudes. Perhaps 
the biggest differences are be- 
cause some hams are attracted to 
the art of ham radio while others 
are attracted to its science. 

The science of ham radio in- 
cludes all the nuts and bolts; the 
different modes available, tech- 
niques for optimizing the utility 
of each mode and, of course, the 
all-important gadgets that go 
along with such pursuits. Those 
folks attracted to the science are 
most comfortable with a solder- 
ing iron in hand, or a computer 
manual in front of them as they 
try to improve performance of 
existing equipment or develop 
new methods, These folks may be 
likely to tweak the equipment and 
then get on the air for brief con- 
tacts so they can determine how 
well the new system is working. 
In some cases, it's name, QTH 
and signal report, and little else, 
then back to the drawing board 
(or out to the antenna farm) to 
figure out the next modification. 

On the other hand, those more 
attracted to the art of the hobby 
tend to be more interested in com- 
munications. In some cases, the 
equipment is viewed as an appli- 
ance to be used rather than as 
something to be disassembled, 
reworked and put back together. 
These folks often enjoy such 

80 73 Amateur Radio Today * July 



the interaction. It is rare to find 
any amateur who doesn't get 
sweaty palms when reading about 
a new high-tech accessory for 
the shack. However, some hams 
see the equipment as a means 
to an end rather than the end in 
itself. This month let's focus on 
the communication aspect of the 
hobby, particularly as it relates 
to public service or disaster 
communications. 

The purpose of such commu- 
nications is to convey a message 
which is accurate, timely and 
complete — most importantly, to 
ensure that the recipient gets the 
meaning that the sender needs to 
convey, This is difficult enough 
when we try to convey our own 
thoughts, but even more so when 
acting as a communicator for 
someone else, In order to be ef- 
fective in such a situation, here 
are a few guidelines; 

* First, most of communica- 
tions is listening. As hams, we 
often love to talk (or type or work 
a telegraph key), but in passing 
message traffic, most of the time 
will be spent standing by. A 
Sky Warn event, for example, is 
often hindered by operators get- 
ting on the air to give "fair 
weather" reports. Likewise, dur- 
ing disaster communications, the 
frequencies become jammed as 
everyone tries to get himself 
heard. The communications chal- 
lenge is to limit oneself to pro- 
viding only the information that 
is requested- 

1997 



• Second, make certain that 
your message is understandable. 
Speak clearly and slowly. Be 
brief. Finally, use language which 
will convey the message. Creative 
phonetics, such as "King Easy 
Eight Yellow Noodles," for ex- 
ample, will just confuse other 
operators. What about "Q" sig- 
nals? Traditionally, the use of Q 
signals is discouraged except 
when using CW, Personally, 1 
have no problem with spoken re- 
quests to "QSY' 1 or acknowledg- 
ing a message with "QSL." Use 
of this lingo is a natural evolution 
for any hobby, particularly a tech- 
nical pursuit. If I want a language 
which doesn't change, Til choose 
Latin. The key question is, does a 
word or phrase help get the mes- 
sage across? If so, it probably 
should be used; if not, avoid it. 

• Third, think about what you 
need to say before you say it. If 
you are used to rag-chewing on 
the local repeater, communicating 
during an event or for a third party 
is more demanding. Exactly who 
is sending the message? Who is 
the expected recipient? Exactly 
what is the message? There is no 
harm in taking a minute before 
you press the push-to-talk switch 
to collect your thoughts. In some 






and the olher station can speak 
directly. 

• Fifth, be supportive. The ham 
radio community is just that — a 
group of people with a common 
interest interacting with one an- 
other. If you need proof, listen in 
on the various repeaters in a given 
area. Each repealer tends to have 
its own personality, reflecting the 
interests and styles of the opera- 
tors who regularly use that ma- 
chine. As a member of a particular 
community it is our responsibil- 
ity to help one another out. If 
someone (particularly a new- 
comer) makes an error in operat- 
ing procedure, help out. It is the 
opposite of communications to 
criticize another ham, especially 
over the very public air waves 
where other hams and people with 
scanners can all hear. 

Finally, as the old joke goes, 
"How do you get to Carnegie 
Hall?" "Practice! Practice! Prac- 
tice f" Although most of us are 
pretty confident of our own abili- 
ties to be effective communica- 
tors, the time to find out is nor 
when a storm or other disaster 
has hit. Check into a local Ama- 
teur Radio Emergency Service 
(ARES) or Radio Amateur Civil 
Emergency Service (RACES) net 



Creative phonetics will just confuse 

other operators. " 



situations it may even be appro- 
priate to take a moment to re- 
hearse before transmitting. This is 
true in any area of communica- 
tions. For example, many student 
pilots are taught to practice what 
they're going to say before con- 
tacting approach control or the 
tower. Sometimes this is very 
helpful and saves stammering 
once on the air. 

• Fourth, if you are communicat- 
ing as a part of a net, follow the net's 
mles and procedures. If a formal net 
has been called, every operator is 
normally expected to contact only 
net control. Once you are acknowl- 
edged, then it is okay to give your 
information. If you need to speak 
with another station t the procedure 
is often to request to "go direct" 
with that station. Net control will 
either give you permission to do so 
and have you stand by, or recom- 
mend another frequency where you 



on at least a fairly regular basis. 
Volunteer to help out at the local 
10k or fun run or a parade. The 
Red Cross may operate first aid 
stations at various events, and rely 
on hams for communication. At 
Louisiana State University, for 
example, hams provide this com- 
munication support during foot- 
ball games, as well as enjoy a bit 
of Tiger football in the bargain. 
This will help you develop the 
skills you'll need, and have some 
fun while you're practicing, 

Communication is not only part 
of the hobby — ii*s an aspect that 
makes us most useful to others. 
The amateur operator and his or 
her communication skills is every 
bit as important as the equipment 
we use. Tweak your communica- 
tions skills as carefully as you 
tune your equipment. It is the 
combination of both that makes 
us the most valuable. 



Number $1 on your Feedback card 



Let's Keep CW Alive! 



It's distinctive, it's useful, and— most of ail— it's fun! 



Arthur R. Lee WF6P 

106 Western Ct. 

Santa Cruz CA 95060 



The skipper, Terry Parks N6NUN, 
pointed the bow of his 32-foot 
Grand Banks trawler toward 
Monterey and headed out into the cold, 
choppy water of the bay. Before going 
below for a hot cup of coffee, I asked 
him if he would put up his 15m whip an- 
tenna so that I could work a link 1 CW, I 
enjoy being on the air when we are at sea 
and wanted to pla\ around and make a 
contact or two, I sat down at the 
navigator's station, fired up the rig, 
tweaked the auto tuner a touch, and ca- 
sually sent out a CQ. The feel of his key 
in the rolling sea was comfortable at 
about 12 words per minute so I stayed at 
that speed. To partially drown out the 
noise of the big dicsel, I pressed the ear- 
phones closer to my head. After I tapped 
out only one call, a moderately readable 



station came back almost immediately. 
We chatted along, exchanging the usual 
information. My QTH, a maritime mo- 
bile in Monterey Bay CA: his QTH — 
Romania ! I was SO startled and delighted 
that I nearly spilled my coffee! After 
about 15 minutes, the band faded so we 
signed off. But wc could never have 
made the contact on voice mode. Need- 
less to say, Terry and I were pretty ex- 
cited about the QSO. 

Anyone for CW? 

CW is a viable and useful language, 
something we hams can be proud of us- 
ing. It's a great language, music to some, 
and a specialized communications skill 
that sets hams apart from the rest of the 
population. If we stop to consider, it is 
the common bond among amateurs that 




Photo A. Copying code off the air can get you hack up to speed. Leave ihe rig tuned to a CW 
practice srahon as background music to get your mind used to hearing code. 



makes us a unique and truly distinctive 
group. At one time or another we all 
worked hard to develop our initial 
threshold speed of 5 wpm, yet a recent 
informal poll of a California amateur ra- 
dio club disclosed that about half of the 
respondents rarely or never used CW. 

As with any language, code must be 
practiced regularly to attain even the 
lowest degree of proficiency. One has to 
be comfortable with the mechanics of a 
language before enjoyment sets in and 
CW is no exception. 

The Novice Enhancement Program 
opened up a portion of the 10 meter band 
to voice. This effectively short-circuited 
the past CW training period for Novices, 
allowing them to go straight to voice. 
This, then, can become a trap, just as at- 
taining the Technician class license and 
acquiring 2m capability was for many 
hams over a multitude of manv vears in 
the past. As an enticement, and on the 
positive side, the major benefit of 10m 
voice privilege is that it gets many 
people on the air who might not be if 
forced to use CW. To some amateurs, 
CW is a painful experience and to be 
avoided at all costs. It doesn't have to be 
that way. In fact, CW can be (and W.\ a 
lot of fun once it is mastered. 

In many discussions with hams, there 
seem to be several basic reasons for not 
using CW. These generally arc given as: 

1 . My code is rusty. 

2. My code speed is too stow. 

3. 1 don't know the proper procedures, 

4, I don* t know what to say. 

5, I don't want my friends to know 
how bad I real I \ am. 

m 

73 Amateur Radio Today * July 1997 81 




mmmaMm 

Photo B* The author, copying CW from 
WlAW code practice broadcasts. Send out a 
CQ on yot4r own or return the call of some- 
one who is sending at your speed of copy. 
Don't he in a rush. Slow copy is fine and gets 
yon going again. 

6. {Now get this one!) I can't spell. 

These reasons are valid to those giv- 
ing them, but they can he overcome vviih 
a little hit of effort. Reason number six is 
easy to get around. First of all, few of us 
can correctly spell every word we use in 
our daily conversations so why worry 
about it? Do your best, abbreviate when 
possible, and lastly, if this is any com- 
fort, you can assume that the receiving 
operator won't mind a few misspellings 
Offer a few "HI His" and let it go at that. 

Things to do 



Here are a few suggestions that might 
help increase your on-lhe-air proficiency 
and enjoyment of CW; 

1. If you haven't been on the air with 
CW tor awhile, a few minutes of off-thc- 
air practice sending will shake out some 
of those cobwebs, Dust off the old key 
and code practice oscillator, relax, and 
send plain text out of the morning news- 




Photo C* Boh Brouwer N6HLE, operating 
his ham rig aboard his 32-foot shop, Cybcle 
II. Bob uses a straight key when at sea as a 
maritime mobile, but prefers his bag for 
shore use. 

82 73 Amateur Radio Today * July 1997 



paper while having your morning coffee. 
Tape your sending for a later playback 
while on your way to work. Be sure to 
include a generous amount of mixed 
numbers. Telephone numbers in the 
classified section are a good place to 
start. Work in some callsigns from con 
test winner listings found in back issues 
of ham magazines. 

2. After a few of these solo practice 
sessions to build up your confidence in 
getting those tough **L"s, "F's, "G^s, 
and "W" sorted out again, turn on the 
receiver and copy some "easy-listen- 
ing" code at your speed. Take it slowly 
at first, but don't spend more than 10 
minutes at any one sitting* 

3. Make a habit of turning the rig on to 
CW whenever you are in the shack. Use 
CW as background music and make no 
conscious attempt at copying — your 
subconscious mind will absorb the 
sounds of the characters by osmosis. 

4. Work a CW contact by answering a 
CQ at your comfortable speed. Go ahead 
and answer — the sending operator, in 
most cases, won't bite you. Remember, 
he or she must want to talk to someone 
or they wouldn't be calling CQ in the 
first place! You can be that someone. 
This is a case where talking to strangers 
is encouraged. I tell my ham radio stu- 
dents that "Slow is good!" You don't 
have to be a speed demon to enjoy CW, 
Good, slow, code is a pleasure to listen 
to. 

5. Make a commitment to yourself to 
work at least one CW contact within a 
given time period. Once or twice a week 
is fine to begin with. The object here is 
to use the skill in an established routine. 
The QSOs can be short, but fun contacts 
are inevitable. 

6. Help a Novice. We were all Novices 
once. Get on the Novice band and work 
with someone who is struggling with the 
code for the first time. Help them over- 
come their fear of being self-conscious 
about their early efforts. Give them a 
few helpful tips if you can. Novices can 
benefit from your past operating experi- 
ence. Remember, you have been in this 
hobby longer than they have, 

1. Set up a CW sked with a friend. He 
or she could live down the street, across 
town, or thousands of miles away. You 
can help each other. When I first learned 
the code. I had the key in one hand and 
the telephone in the other, repeating 
back a string of numbers or callsigns my 



radio friend had just sent. 

8. As your confidence with CW 
grows, push yourself a bit. Copy WI AW 
and some of the better code operators at 
speed higher than you think you can 
copy. Stretching is good exercise, 

9. Take a chance. Contact someone 
who sends a bit faster than you can copy. 
Send a QRS if things get sticky. They 
will be glad to stow down if you only 
ask. After awhile, you will be pleasantly 
surprised that you can copy faster than 
you thought. 

10. Initiate your own CQs, Grab the 
bull by the horns and go for it You know 
what to do — you yourself have been 
trained by someone at one time or an- 
other. It is probably good to remember 
thai you can do no wrong* a far as proto- 
col goes. A CW friend once told me to 
pretend you are simply talking, only you 
are using your new language. About the 
only procedural rules you will have to 
observe will be to stay within the ham 
bands and to send your catlsign at the 
proper limes. Use the rag-chewer's 
tried-and-lrue guideline of just saying 
anything that comes into your mind! 

As for voice communications, anyone 
can talk and most of us have been doing 
this since about age three. Household 
telephones and voice bands are excellent 
means of transferring information, yet, 
as hams, we must not overlook the bond 
that holds us together. We have that rare 
something that not everyone has — the 
ability to make ourselves understood in 
a unique way. CW is far from dead and 
can be richly rewarding if we work at it a 
bit. Give it a try — only through regular 
use can it be made easy. 



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The old, hard way, to learn the code is 
to start slow and gradually speed up. In 
that direction lies madness. The Blitz 
Method is to start at 13 or 20 wpm im- 
mediately. Yes, tapes are available to 
help. Use T-5 to leant the characters. T- 
13 will get your General ticket with a 
few hours work. T-20 ditto for Extra, 
The tapes are $7 each and are as nasty 
as Wayne could make them. 



Number 83 on yaur Feedback card 



Help for College-Bound Hams 



Apply for an amateur radio scholarship. 



Matt Minney N8PGI 

RL 1 Box 126 

Shock WV 26638 



Students entering college are al~ 
nays interested in extra money, A 
ham radio operator has several op- 
tions for finding college scholarships, 
and the opportunities are growing every 
year. If you qualify for one of these 
scholarships, you'll be one step closer to 
paying lor your college education. The 
requirements for applying for a scholar- 
ship are generally not prohibitive and 
simply require filling out an application 
for review by committee, 

What's available? 

Amaieur radio scholarships generally 
come from one of three sources: The 
ARRL Foundation, the Foundation for 
Amateur Radio, and Da v ton Amateur 
Radio Association. All work in a simi- 
lar manner, but each one has unique 
characteristics. 

The Dayton Amateur Radio Associa- 
tion, the group that sponsors the Dayton 
Ham vent ion, offers several scholarships 
to students who graduate from high 
school in ihe year for which they are ap- 
plying. These scholarships are about 
$2,000 per recipient. 

The Foundation for Amateur Radio, 
located in College Park. MD. represent 
nearly two dozen organizations with di- 
verse requirements and awards. The re- 
quirements var> for each scholarship, 
but several of these are available for ev- 
ery amaieur. Some scholarships arc 
available only to hams in a specific field 
or particular geographic area, such as a 
county or a state; in this case, being a 
graduating high-school senior is not re- 
quired. The available amount begins 
around $500 and peaks at $2,000. 

The lasi of the three major sources is 
the ARRL Foundation. This group is 
supported by the ARRL, and is based at 
ARRL Headquarters in Newinglon, CT. 
The ARRL Foundation also offers a vari- 
ety of scholarships that have different 



requirements for eligibility. There are 
both general scholarships and those tar- 
geted to specific groups of hams. These 
again have geographic or academic re- 
strictions. The scholarships available 
could again vary from $500 to S2XXXL 

What's involved? 

Although each of the three major or- 
ganizations has somewhat different rules 
and procedures, the processes are basi- 
cally the same. There arc usually about 
five general parts in most applications: a 
basic application, financial information, 
references, a transcript, and an essay, para- 
graph, or some other example of written 

"Work out your answers on a 

separate sheet of paper before 

you fill out the application. 



y? 



material by the applicant. These may be 
part of the main application or separate 
forms, depending on the application. 

Filling out the main application is the 
most important pan of the process. This 
part of the process includes personal in- 
formation. Questions thai will appear in- 
clude basics such as the persons name 
and the name of the institution that is be- 
ing applied to. There are also questions 
about the applicant's academic career 
and standardized test scores. I suggest 
that the applicant work out the answers 
on a separate sheet of paper before fill- 
ing out the application form. This will 
allow polishing any answers. Open- 
ended questions that ask why you and 
not someone else should receive the 
scholarship require serious thought. 

A statement of the applicant's finances 
is a relevant question in scholarship 
applications. The best source to answer 
this question is last year's tax returns. 
The application will also want a 



projection of the need for the upcoming 
school year, Before giving a final figure 
include any realistic expenses that might 
be encountered, not just the tuition. Fi- 
nally, some applications ask for informa- 
tion about other items such as special 
needs and real property such as cars. Be 
honest when answering these questions. 
but be careful to not provide answers 
that you believe the committee wants to 
hear. 

The third component of an application 
for a scholarship is a set of references. 
Usually these references will come in 
two forms; one being for some aspect of 
the candidate's personality and one rec- 
ommendation for a specific scholarship. 
The references for ones personality or 
character could entail as many as three 
different sources. Make every effort to 
include any information that will make it 
easier for the committee to locate your 
reference. It is a good idea to talk to your 
references ahead of time so they arc 
prepared for the possible phone call. 
Secondly, some specific scholarships re- 
quire a recommendation from a member 
of the sponsoring organization. Try to 
find a member in a local club or area net 
if there is no member of the organization 
in the area. 

The fourth part of most scholarship ap- 
plications is a transcript. There may not be 
a transcript requirement, but including one 
is a good idea. A high school student 
should ask the guidance counselor to pro- 
vide a copy if needed. This will help to an- 
swer some questions about overall grade 
point average or test score questions. 

The last major part of a scholarship 
application involves some sort of writ- 
ing. This is a broad category that might 
range from a separate description of your- 
self to a paragraph that is the main 
application. This gives the scholarship 
committee some idea as to the appli- 
cant's writing ability and a hint about the 

73 Amateur Radio Today ■ July 1997 83 



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person behind the application. It is a good 
idea to include as much in the space as 
alio wed but make sure that the included 
material is something that the committee 
needs to know. Again, write as many drafts 
as needed on scratch paper, then present 
the best answer 

Helpful hints 

A minor detail might not be the differ- 
ence between receiving and not receiving 
a scholarship, but it is always good to gen- 
erate as few problems as possible. Minor 
changes can make the application easier to 
read and more attractive to the committee. 

A typed application is generally appreci- 
ated by most people, unless the applicant 
has excellent penmanship. There are two 
major benefits to typing the paper First, it 
will be easier to read, and the second is 
that the application will appear much 
neater. Another simple hint is to finish the 
application as quickly as possible. This 
means asking for the references and tran- 
scripts ahead of time, This also gives the 
applicant time to make minor changes as 
needed. Writing out the answers to the ap- 
plication questions on a separate paper will 
make revisions much easier. Most appli- 
cations require a copy of the applicant's 
amateur license, so be sure it is included. 

Once the application is complete, 
make a last-minute checklist of all the 
elements that need to be included. Check 
the address and send it in several days 
before the due date, A late application 
may not be accepted. Scholarship win- 
ners will be notified by phone or by mail 
as to the specific scholarship and the 
amount. Winners may also be recog- 
nized by an amateur magazine or bro- 
chure. Instructions as to how to receive 
the scholarship will also be included in the 
notification. This usually involves sending 
the check to either the winner or to the 
institution listed on the application. 

Any ham radio operator planning to 
continue his or her education beyond high 
school should consider applying for a 
scholarship, There are no guarantees of re- 
ceiving any help with college expenses, 
but a well-done application is a definite 
step toward being the winning applicant, 

I would like to acknowledge the use of 
each organization's scholarship materi- 
als in the creation of this article. I also 
wish to express gratitude for the help 
they gave to me in the completion of m 
college degree. 



i 



CIHCLE 184 ON READER SERVICE CARD 



Never sry die 

Continued from page 31 

outsource, there's a huge and 
growing need tor the creation of 
new jobs. 

The main problems facing entre- 
preneurs in starting new businesses 
i unless they've react my hook. Mak- 
ing Money. A Beginner s Guide* *md 
have followed my instructions) are 
getting funding and gaining the busi- 
ness skills needed lor success. I have 
a sneaky proposal for helping to 
solve both of these problems. 

The idea is to get a group of 
synergistic businesses together 
to form a support group. Almost 
all small businesses need sup* 
port services such as lawyers, 
accountants, computers, office 
equipment and supplies, print- 
ing, advertising, maintenance, 
waste removal, telephones, in- 
surance, office space, and so on. 

Using the business expertise 
of such a supporting group, say 
as a board of directors, a new 
business can hardly fail. And 
since it doesn't cost a lot to get a 
new small business going* the 
startup funding could come from 
a fund put together by the sup- 
porting group. I"d call it a con- 
sortium, except for the negative 
connotations of "con/' so let's 
call it a "pro*"sortium. 

Step two for the support group 
would be to get their state to set 
up L» small business development 
administration to provide the 
needed funding — and to do this 
on a for-profit basis. I would ask 
the support prosori turns to in- 
demnify the state for any losses. 
This would act as a filter to weed 
out questionable startups. 

Clubbing Us 

Proof that Wayne's basic 
guide to politics (Never Re-elect 
Anyone) works with your local 
ham club as well as a way to 
flush the Washington toilet 
you've allowed to back up ar- 
rives almost daily in letters from 
readers. Like how about the club 
president who has ordered that 
the club phone patch is for emer- 
gency assistance and not a sub- 
stitute for a cellular phone? 
Sure, we do almost as well as 
CB when it comes to dealing 
with emergencies, but this is still 
a hobby and that means it's sup- 
posed to be fun. If the club re- 
peater lends to get bogged down 
with club members making calls 
to their families, then put in an- 
other repeater. Good grief! 

How much of an effort have 



your club officials made to bring 
in youngsters? Most of the clubs 
Fve visited are almost all 
peopled with old men with one 
foot on a banana peel and the 
oilier already in the grave. 
There' 11 be lots of good deals on 
used ham gear soon. A few years 
ago 1 remember being amazed 
when 1 spotted a youngster 
wandering around at Dayton. 
Wow! 

Mooned Again 

A press release from the SETl 
League announced their collabo- 
ration with the Artemis Society 
with the goal of placing a radio 
telescope on the back side of the 
Moon. In order to buy into this 
project one has to be a pathologi* 
cal skeptic about both LTOs and 
contactees* Which, to my mind 
means that one has to be se- 
verely unread on the subject. 

1 often marvel at the blind 
spots many scientists have — at 
their inability to even investigate 
anomalies which to me arc cry- 
ing out for attention. Heck. 1 re- 
ported around 30 years ago in 
my editorial the results of my in- 
vestigating a local crop circle. I 
interviewed the family living 
next to the field and heard about 
a UFO which silently hovered 
over their home for several min- 
utes before going up and circling 
the nearby Crotched Mountain 
Rehabilitation Center, where it 
was seen by hundreds of people. 

I do have to admit, as Fvc 
read the stories of contactees and 
talked with several personally, 
that Fm damned annoyed that I 
haven't been picked by the KTs 
for the experience. Perhaps they 
recognize that Fd keep them too 
busy answering my questions to 
be of much help. 

Hither a bunch of people, many 
with some impressive credentials, 
are secret I \ crazy, or the contactee 
experience is a reality. And that 
means that the aliens are not only 
here, but thai they've been visiting 
us for a tong t long time. 1 suspect 
our recent technology advances 
may have increased their interest, 
hence the recent step-up in 
sightings of LTOs and our hearing 
more about contactee experiences. 

Now, getting back to the 
Moon. Until I see some good 
solid scientific refutation of the 
case Rene has made that we've 
never been to the Moon, the idea 
of human space travel beyond a 
near orbit inside the protective 
shield of the Van Allen belt 
seems implausible. So the whole 



concept of installing and man- 
ning a radio telescope on the 
Moon's butt seems to me like 
just another scam to solicit funds 
from the uneducated credulous, 

The Ham Impact 

1 keep rattling on, preaching 
to the choir about how much ad- 
venture amateur radio has 
baiught me. So how about you? 
How has amateur radio changed 
your life? In business? In adven- 
ture? Friends? Get busy at your 
word processor and write about 
it. Give me some ammo to use in 
selling kids on our hobby, Fd 
love not just to print an article in 
73 on the impact of hamming on 
your life, but maybe to gather a 
bunch of stories into a book so 
we can reach out and get the 
public aware of what a powerful 
hobbv we have. 

m 

Even skiing down the slopes 
in Aspen this last January with 
some local hams was an adven- 
ture for me, English is an impov- 
erished laneuaec when it comes 
to expressing feelings, so I can'i 
adequately describe the thrill 
that I get when Fm zooming 
down a mountain with friends. 
Sure, bowling is fun when 
you>e good at it, but skiing pro- 
vides a rush ihafs beyond 
words. It's addictive, 

So tell me about the adven- 
tures that amateur radio has pro- 
vided you — how it's provided 
you with n career path. And get 
cracking, I don't want lo have to 
keep reminding you, fighting 
your almost legendary ability to 
procrastinate, 

Those ARRL Proposals 
(Rearranging the Deck 
Chairs) 

You've probably read or heard 
about the rule changes the ARRL 
has suggested. 

Look, there's one simple 
problem that has to be solved if 
amateur radio is going to be 
saved from extinction. We either 
gel a whole lot more hams or we 
gel blown away. Alas, to no 
one's surprise, the ARRL pro* 
posed rule changes are insignifi- 
cant tinkering — designed more 
to create controversy among the 
hidebound than to solve our 
problem. It gives the facade that 
the League is doing something. 

There are two major reasons 
why the public interest in ama- 
teur radio has gone from a bright 
fire to a small spark — from the 
time when there was prestige in 



being a ham to today's public 
yawn, they're not too sure what 
ham radio is. Reason number 
one is an almost total lack of 
promotion of the hobby. Number 
two is the continued mainte- 
nance of the code as what is all 
too often perceived as an insur- 
mountable — a hazing — obstacle. 

Sure, back in the 1930s, when 
1 eot interested in the hobbv, and 
90% of all ham contacts were 
via CW, there was some ratio- 
nale for making sure thai new 
hams knew the code. It didn't 
make a lot of sense to me then, 
since if J wanted to be active on 
CW I would have to learn the 
code, with or without a code test 
as pan of the qualification. 

Lowering the 13-per test lo 
1 0-per isn't going to do anything 
magic. Sure, the League will be 
able to continue to make money 
selling code courses, but it isn't 
likely to attract many more 
hams. 

We need articles about ham- 
ming in the newspapers, in 
popular magazines, on TV, and 
so on. When 1 get on the Art Bell 
show and talk about amateur ra- 
dio, I gel thousands of letters 
horn listeners wanting to know 
more, W T e have one of the best 
hobbies there is, and I've had a 
bunch of hobbies, so 1 know 
what Fm talking about. Amateur 
radio can help to provide a ca- 
reer path for youngsters that's 
right in tune with the times. It 
can provide adventure for hams 
of any age, As 1 keep explaining, 
amateur radio has provided me 
with a lifetime of adventure and 
friends. 

What could be more fun for a 
ham than publishing a ham 
magazine? Fve used lhai plat- 
form to visit hams in over a hun- 
dred countries and to operate 
from some really weird places. It 
was my contacts with Robbie 
5Z4ERR in Nairobi that got me 
to organize a ham hunting safari. 
What a blast that was! Wow! I 
still remember the moment when 
Larry slipped on the wet moss 
and came tha-a-at dose lo fall- 
ing into Murchison Falls in 
Uganda! And it got me to be a 
member of the US delegation at 
the International Telecommuni- 
cations Commission in Gen- 
eva, It got me two weeks of op- 
erating from the king's palace in 
Amman, alone with dinner with 
the king and queen of Jordan. It 
got me operating a ham station 
from the US Embassv in Iran, 
and from the DMZ between 
North and South Korea. 



73 Amateur Radio Today * July 1997 85 



My success in helping ham re- 
peaters with endless articles and 
books turn into a leading ham 
activity, which then spawned 
cellular telephones, got me to 
stan Byte to help personal com- 
puters grow from a curiosity into 
a new industry. 

And there isn't anything that 
I've done that anyone else 
couldn't have. 1 didn't start out 
with any money from my family. 
I always just barely squeaked 
by in school. Well, 1 did gel in- 
volved with extracurricular ac- 
tivities a lot. Like the radio club, 
the Savoyards (singing Gilbert 
and Sullivan), the Choral Club, 
the Philharmonic Choir of Brook- 
lyn, the camera club, stuff like 
that. 

So, after all the adventure 
amateur radio has provided mc, 
I really hate to see the hobby be- 
ing destroyed by the League 
— through a religious obsession 
with the code and an almost 
complete neglect of promotion. 

Books for Crooks 

The Art Bell (W60BB ) show 
hits all 50 states, plus a good 
deal of Canada, via around 335 
AM radio stations, The down- 
side is that he's on for five hours 
starting at 11 p.m. Pacific time. 
That's from 2 a.m, in the east. 
Art's interviewed me three times 
so far and, judging from the re- 
sponse, his audience is biased 
towards older people, who tend 
to have trouble sleeping, truck 
drivers on long-haul trips, and 
prison inmates, 

I encourage the people writing 
to tell me something about them- 
selves. Fve been surprised at the 
literacy and intelligence of many 
of the letters from prisoners. But 
they have a big problem: no 
money. Many really want to edu- 
cate themselves, so they've been 
sending stamps to buy my guide 
to self-education, which is a re- 
view of around a hundred books 
about things they don't teach in 
school, but should. 

These are not the kind of 
books they're going to find in 
their prison libraries, so how can 
they take the next step? Td love 
to try and do something about 
this, but 1 can't handle every- 
thing I've already signed up to 
do. I envision a "Books for 
Crooks" program, run by some 
altruistic retired person who 
would like to score some points 
with St. Peter. The idea would be 
to buy some books and send 
them to inmates who will (a) 

86 73 Amateur Radio Today • July 



promise to read them; (b) make 
notes on the contents; (c) return 
them within a week; (d) and pay 
$5 for each book they've read 
into a revolving fund after 
they've been released. 

The program would need one 
person to handle the "rentals," 
and someone with the bucks to 
endow the startup of the opera- 
tion. A hundred hooks might run 
$LQ00 for the original inven- 
tory, though Fin sure that many 
publishers might cooperate with 
big discounts. 

Of course our whole prison 
system needs an overhaul, k is 
not correcting behavior And* as 
I\m sure you know by now, 
America has the largest percent- 
age of its population in prison oT 
any country in the world. Is that 
a hint that we have a problem? 
Please let me know if you're in- 
terested in helping to solve this 
problem. It needs to be done and 
Vm beginning to realize that 1 
can't do everything. 

Guts 

After reading a bunch of let- 
ters from Art Bell show listen- 
ers, many from hams, 1 feel like 
preaching. The basics of my ser- 
mon today are simple. First, our 
educational svstem is not edu- 
eating. Second, our health care 

mm, 

system is not keeping us healthy. 
Third, our monetary system is a 
fraud. Fourth, our "correctional 
system'' doesn't correcl any- 
Ihing. Fifth, our Congress is 
mainly a bunch of ex-lawyers 
getting rich on bribes from lob- 
byists. Sixth, the administration 
isn't any better. And unless you 
have the guts to do something 
about it personally, amateur ra- 
dio is going to go down the tubes 
with our frequencies sold to the 
highest bidders, which aren't go- 
ing to be us. The ARRL is doing 
almost nothing to help save our 
bands, so who does Lhat leave? 

Oh, you whine, but what can 
just one person do? Step one is 
to do your homework so you 
know what you are talking 
about, Step two is to get yourself 
into gear and start making things 
change. One person can make a 
hell of a difference; it's just that 
so few people ever try. The mov- 
ers and shakers do just that — - 
they move and shake things up. 
But first you have to know what 
you are talking about and where 
best to put the pressure to gel 
change. 

It's a lot of work to become a 
world expert on some subject, 

1997 



but ridiculously easy to become 
an area expert. 

Know what you're talking 
about and Lhen stan talking — 
and writing. Raise hell and put a 
brick under it. Our school sys- 
tem doesn't have to be one of the 
worst in the developed world. 
Our health care system doesn't 
have to be worse than many 
third- world countries' and be the 
most expensive in the world. 
Our prisons don't have to house 
the largest percentage of our 
population of any country in the 
world. You let all this happen. 
We don"t have to have more 
government workers (and I use 
the term loosely) than we have 
in manufacturing. 

Find out for yourself why any 
one of these disgraces has hap- 
pened and stan doing something 
about it. 

Maybe you'd prefer to start 
with something less intimidat- 
ing — so how about finding out 
for yourself what the situation is 
regarding the potential life of 
amateur radio? Don't believe 
me — do your homework — then 
start doing something about it. 

All it takes is guts to change 
things. Got any? 

Distant Learning 

Technology is improving our 
ability to learn wherever we hap- 
pen to be. We have books, audio 
tapes, video tapes, and TV, My 
favorite is books. You can't 
highlight audio or video tapes, 
or get to the part you want 
quickly via an index. And you 
can't throw nearly as much in- 
formation into your suitcase 
when you* re off on a trip. 1 al- 
ways have a stack of books with 
me when [ travel. 

There are some things which 
really require video, like the 
learning of some skills. A few 
years ago I had the idea of put- 
ting the whole K-12 curriculum 
on video tapes, with each course 
being taught by a performer so it 
would be exciting. Even the oth- 
erwise most boring courses can 
be made exciting by a good per- 
former. In this way the very best 
teachers in the world could be 
tapped. The unions would fight 
this to the death. 

I had this crazy idea that this 
would be a great project for a 
university, providing K-12 
courses for any parents really in- 
terested in seeing their children 
actually learn and have fun do- 
ing it. Kids could leave their 
classmates behind in the dust. As 



John Taylor Gatto, the prize- 
winning teacher, points out: It 
only lakes about a hundred hours 
for a child to learn to read and 
write, 

John quit teaching, saying that 
he couldn't keep doing that to 
the kids. Fve reprints of two of 
his talks, which go into what's 
wrong with our school system 
and why it is doing so much 
damage to our kids, $3 from 
Radio Bookshop. 

Another War Lost 

Hmm, let's see now. Which 
president declared a war on 
drugs? Well, we Lost it, Johnson 
declared war on poverty. An- 
other lost war. Nixon declared 
war on cancer. So here we are 26 
years later, with $32 billion sup- 
posedly spent on cancer re- 
search, and more people are dy- 
ing from cancer today than in 
1971. Those vaunted cancer 
drugs? All they do is give the pa- 
tient a few more months of pain- 
ful life. One in three Americans 
will get cancer and a half million 
will die this year. 

Cancer, as I've mentioned be- 
fore, is not caused by God. We do 
it to ourselves through poisoning 
our bodies and malnutrition, 

Poisoning ourselves? Like 
smoking, lor instance. Malnutri- 
tion? Just look at Ihcjunk people 
are taking through the checkout 
counters at the market for their 
families and you'll see why 
heart disease is the number one 
killer, with cancer closing in 
last. You wouldn't mistreat your 
car the way you do your body. 



Radio Bookshop 



FlMMfre #00-274-7*73 or 603-^24 005 B- FAX 
603-5*24-1461 3, or f;ec nriter form on psige K8 
1<ir i injuring information . 



Rene's Books 



NASA Mooned America. 
Rene makes an airtight case 
that NASA never landed any- 
one on the moon. Ridiculous, 
of course, so maybe you can be 
the first to find fault" with 
Rent's 30 "gotchas." He sure 
convinced Wayne. $28. 

The Last Skeptic of Science. 

Rene blows holes in one cher- 
ished scientific dogma after an- 
other Do you believe there 
have been ice ages? That the 
moon causes the tides? That the 
iron core of earth causes il& 
magnetic field? That the trans- 
mutation of elements is diffi- 
cult? Another $28 well spent. 



Number 87 an your Feedback card 



Prophohtion 



Jim Gray W1XU 
210 E Chateau 
Payson AZ 85541 

As I write these words in mid- 
April (and you read them in June), 
July propagation is particularly 
difficult to predict. Last week, 
Old Sol suddenly awakened from 
his long sleep and produced ma- 
jor solar flare activity — the great- 
est in years — accompanied by 
groups of sunspots breaking out 
on the solar disc. While this is 



encouraging news, the old saying 
4l one swallow doesn't make a 
summer" still applies, because 
there is no assurance that the re- 
newed activity will continue or 
increase over the next three 
months. 

However, my best guess is that 
the ho-hum conditions of the past 
two years have changed and 
we can expect to see greatly 
increased DX opportunities 
beginning this fall. 



EASTERN UNITED STATES TO 



GMT; 


00 


02 


04 


06 


08 


10 


12 


14 


16 


18 


20 


22 


ALASKA 












20 


20 












ARGENTINA 


20 


20 


20 


40 






20 


20 


15 


15 


15 


15 


AUSTRALIA 




20 


20 


20 


40 


40 


20 










CANAL ZONE 


15 


40 


40 


40 


40 


40 




15 


15 


15 


10 


10 
20 


ENGLAND 






40 


40 






20 


20 


20 


20 


20 


HAWAII 






20 




40 




20 


20 










INDfA 




















- 


JAPAN 














20 


20 










MEXICO 


15 


40 


40 


40 


40 


40 




15 


15 


15 


10 


10 


PHILIPPINES 














20 












PUERTO RICO 


15 


40 


40 


40 


40 


40 




15 


15 


15 


10 


10 


RUSSIA (C.I.S.) 














20 


2C 




20 






SOUTH AFHICA 






40 


40 




20 


20 








20 




WEST COAST 


20 


| 40 


40 


40 


40 


40 


40 










20 






J_UN 






iS" 


rA 


TES" 


ro: 


CENTI 


RA 


(IT 


ED 


ALASKA 




20 


20 










20 


20 








ARGENTINA 


15 


20 


20 


40 






20 


20 




15 


15 


15 


AUSTRALIA 


15 


20 


20 


20 


40 


40 




20 






20 




CANAL ZONE 


15 


20 ' 20 


20 


40 


40 


20 


20 


15 


15 


15 


10 


ENGLAND 


20 


40 










20 


20 




20 


20 


20 


HAWAII 


15 


15 


20 


20 


20 


40 


20 


20 










INDIA 












1 












JAPAN 


20 


20 








20 


20 








MEXfCO 


15 


20 


20 


20 


40 


40 


20 


20 


15 


15 


15 


10 


PHILIPPINES 




20 


20 








20 


20 










PUERTO RiCO 


15 


20 


20 


20 


40 


40 


20 


20 


15 


15 


15 


10 


RUSSIA (ai.s.) 
















20 






20 




SOUTH AFRICA 














20 






^^^^^^^ 


20 


20 



WESTERN UNITED STATES TO: 


ALASKA 




20 


20 












20 








ARGENTINA 


15 


20 


20 


40 


40 






20 


20 




15 


15 


AUSTRALIA 




20 


20 


20 


20 


40 


40 




20 




15 


15 


CANAL ZONE 


15 


15 


20 


20 


40 


40 




20 


20 


15 


15 


15 


ENGLAND 


20 














20 


20 






20 


HAWAII 


20 


15 


15 


20 


20 


20 


40 


40 


20 




20 


20 


INDIA 








20 










20 








JAPAN 




20 


20 


- 










20 








MEXICO 


15 


15 


20 


20 


40 


40 




20 


20 


15 


15 


15 


PHILIPPINES 








20 








L 


20 






PUERTO RICO 


15 


15 


20 


20 


40 


40 


_^_^_, 


20 


£0 15 


15 


15 


RUSSIA (C.I.S.) 


















20 








SOUTH AFRICA 






40 












20 








EAST COAST 


20 


40 


40 


40 


40 


40 












20 



JULY 1997 

SUN MON TUE WED THU FRI SAT 






1 G-F 


2 F 


3 F-P 


4 P 


5 P-F 


6 P-F 


7 F 


8F 


9 F-P 


10 P 


11 P-F 


12 F 


13F-G 


14 G 


15G 


16G 


17G 


18 G 


19G 


20 G 


21 G-F 


22F-P 


23 P 


24 P 


25 P 


26 P 


27 P 


28 P-F 


29F 


30 F 


31 F 







This month's calendar shows 
seven days when propagation is 
likely to be Fair, six Poor days, 
seven Good days, and eleven 
trending days: four trending 
toward downward and seven 
trending upward. 

The 4th, 10th, and 23rd through 
27th are likely to exhibit a very 
uncooperative and disturbed 
ionosphere because of other geo- 
physical upsets occurring on 
earth, such as unusual weather 
and the onset of a violent hurri- 
cane season, for example. 

Your best DX opportunities are 
likely to occur between the 14th 
and 20th, so stay alert and make 
the best of your chances during 
this period. Since July is the be- 
ginning of the vacation season, 
and mobile-portable hamming is 
at its peak, plan on having lots of 
fun with both DX and short skip 
wherever you may be! W1XU. 

Band-by-band propagation 
this month 



10-12 meters 

Occasional intense sporadic-E 
propagation may provide open- 
ings to 2,000 miles or more, while 
frequent short-skip openings out 
to 1 ,000 miles or so can occur on 
Good (G) days. 

15-17 meters 

Frequent short-skip openings 
to 1 ,500 miles and occasional 
long-skip openings on north- 
south paths across the equator are 
expected on Good (G) days, 

20 meters 

DX to all parts of the world can 
be expected on this band from 



sunrise to sunset on Good (G) 
days, with peak conditions 
usually occurring a few hours af- 
ter sunrise, and again in the late 
afternoon. Short skip to 2,000 
miles or so may be expected as 
well. 

30-40 meters 

Consistent nighttime DX to all 
parts of the world is expected 
from sunset to sunrise, with pos- 
sible exception of poor reception 
due to high static levels during 
thunderstorm activity, Short-skip 
openings averaging 500 miles 
during the daytime and L500 
miles at night are anticipated. 

80-160 meters 

Nighttime DX on 80 and 160 
can be fair this month, with the 
exception of high noise levels on 
both bands from thunderstorms. 
Daytime short skip of a few hun- 
dred miles is possible on 80 but 
not on 160. Short-skip propaga- 
tion is expected at night on each 
band, and ought to be fair out to 
perhaps 1,400 miles or so, but 
limited by QRN. 



WANTED 

Fun, easy to build 

projects for 

publication in 73. 

For more info, 

write to: 
Joyce Sawtelle, 

73 Amateur Radio Today, 

70 Route 202 North, 
Peterborough NH 03458. 



73 Amateur Radio Today • July 1997 87 



Number 88 on yoor Feedback card 



Barter 'n' Buy 



Turn your old ham and computer gear into cash now, Sure, you can 
wait for a hamfest to try and dump it, but you know yoult get a far 
more realistic price if you have it out where 100.000 active ham po- 
tential buyers can see ft, rather than the few hundred local hams who 
come by a flea market table. Check your attic, garage, cellar and 
closet shelves and get cash for your ham and computer gear before 
It's too old to sell. You know you're not going to use it again, so why 
leave it for your widow to throw out? That stuff isn't getting any 
youngeri 

The 73 Flea Market, Barter W Buy. costs you peanuts (almost) — 
comes to 35 cents a word for individual (noncommercial!) ads and 
$1.00 a word for commercial ads. Don't plan on telling a long story. 
Use abbreviations, cram it in. But be honest. There are plenty of 
hams who love to fix things, so if it doesn't work, say so + 
Make your list, count the words, including your call address and phone 
number. Include a check of your credit card number and expiration. If 
you're placing a commercial ad, include an additional phone number 
separate from your ad. 

This is a monthly magazine, not a daily news p ape r T so figure a couple 
months before the action starts: then be prepared. If you get too many 
calls, you priced it low. If you dont get many calls, too high. 
So get busy Blow the dust off, check everything out T make sure it still 
works right and maybe you can help make a ham newcomer or re- 
tired old timer happy with that rig you re not using now. Or you might 
get busy on your computer and put together a list of small gear/parts 
to send to those interested? 

Send your ads and payment to: 73 Magazine* Barter *n* Buy, 
70 RL 202N, Peterborough NH «3458 and get sel for the phone 

calls. The deadline for the October 1997 classified ad section is 
August 12th, 1997. 






Help 



the kids learn about the wonderful world of ham 
radio. Then well have the engineers well need for 
the next century here in the USA. 

Give a 73 Magazine gift subscription to the 

school in your neighborhood ...only $24.97. Call 
800274-7373. 




$0 



TWEC6S A DI-SCLfilWER Okl TWIS lUVOICC^ IT 
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TAlUED THROUGH MOCMAL IMPOET tRAMMElA 11 

88 73 Amateur Radio Today • July 1997 



Audio Equipment wanted, 1930s - 
1960s. Tube -type amplifiers, large or 
small speakers, mixers, microphones, 
tubes, parts, etc. Especially Western 
Electric, Jensen, Marantz. Mcintosh, 
J,B,L. etc. 1-800-251-5454. BNB202 

HEATH COMPANY is selling photo- 
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authorized source for copyright manu- 
als. Phone (616) 925- 5899, 8-4 ET 

BNB964 

HEATHKITS WANTED: Premium 
Prices paid for unassembled Heainkits. 

Rob W3DX (804) 971-6812 evenings 
or [Robcap@aoi.coml BNB206 

TIRED OF IRONING? PCB service. No 
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PROTO, 4201 University Drive. #1Q2 t 
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ASTRON power supply, brand-new w/ 
warranty. RS20M S99, RS35M $145. 
RS50M $209, RS70M S249, Call for 
other models (818)286-0118. 

BNB411 



BREAK THE CODE BARRIER; A self' 
hypnosis tape that allows you to learn 
or increase code speed easily and 
quickly. To order send $14.95 + $3.00 
S&H to Dr, Hal Goodman, P.O. Box 
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send SASE or [http://www.nemaine 
.com/w3uwh/morse.htm]. BNB2031 

MAHLON LOOMIS. INVENTOR OF 

RADIO: oy Thomas Appleby. (Copy- 
right 1967). Second printing available 
from JOHAN K V* SVANKOLM N3RF 
SVANHOLM RESEARCH LABORA- 
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with S5.00 tor S&H. BNB420 

RF TRANSISTORS TUBES 2SC2879, 
2SC1971. 2SC1972, MRF247, 
MRF455, MB8719, 2SC1307, 
2SC2029. MRF454. 2SC3133, 
4CX250B. 12D06. 6KG6A, etc 
WESTGATE, 1-800-213-4563 

BNB6000 

FM MICRO/LOW POWER BROAD- 
CASTING S8-1 08MHz. PLL Transmit- 
ters/R.F. Amplifiers/Antennas. Mono/ 
Stereo. 50 mWs to 100 Watts. Free 
Catalog/Info. Call (250) 642-2859 or E- 
Mail: [kscot1@pinc.com] R. Scott 
Communications Ltd. We Ship 
World Wide From Canada! BNB1Q2 



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Radio Bookshop 

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elephone: 603-924-0058, 800-274-7373. FAX 603-924-8613 
il: Raefa Bookshop. Dept 797. 70 Route 202 N, Reiertwrough NH 03458 

J D YES. Send me 1 2 issues of 73 at the low rate of 
I $24.97 (save 47% over the cover price). Canada add $7 
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1 60-10 Meters PLUS 6 Meter Transceiver 




Fifteen reasons why your next HF 
transceiver shouid be a JST-245* . 



1 All-Mode Operation (SSB,CW.AM,AFSK.FM) on all HF amateur 
bands and 6 meters. JST-145, same as JST-245 but without 6 
meters and built-in antenna tuner. 

* JST-145 COMING SOON * 

MOSFET POWER AMPLIFIER • Final PA utilizes RF MOSFETs 
to achieve low distortion and high durability. Rated output is 10 
to 150 watts on all bands including 6 meters, 

AUTOMATIC ANTENNA TUNER • Auto tuner included as 
standard equipment. Tuner settings are automatically stored 
in memory for fast QSV. 

MULTIPLE ANTENNA SELECTION • Three antenna connec- 
tions are user selectable from front panel Antenna selection can 
be stored in memory. 

GENERAL COVERAGE RECEIVER • 100 kHz-30 MHz, plus 48- 
54 MHz receiver. Electronically tuned front-end filtering, quad- 
FET mixer and quadruple conversion system (triple conversion 
for FM) results in excellent dynamic range (>1 OOdB) and 3rd order 
ICPof+20dBm. 

6 IF BANDWIDTH FLEXIBILITY • Standard 2.4 kHz filter can be 
narrowed continuously to 800 Hz with variable Bandwidth Control 
(BWC). Narrow SSB and CW filters for 2nd and 3rd IF optional. 

7 QRM SUPPRESSION ■ Other interference rejection features 
include Passband Shift (PBS), dual noise blanker, 3-slep RF atten- 
uation, IF notch fitter, selectable AGO and all-mode squelch 



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8 NOTCH TRACKING • Once tuned, the IF notch filter will track the 
offending heterodyne ( ^ 1 Khz) if the VFO frequency is changed. 

9 DOS PHASE LOCK LOOP SYSTEM * A single-crystal Direct 
Digital Synthesis system is utilized for very low phase noise. 

I CW FEATURES • Full break-in operation, variable CW pitch, built 

in electronic keyer up to 60 wpm. 

I I DUAL VFOs • Two separate VFOs for split-frequency operation. 
Memory registers store most recent VFO frequency , mode, band- 
width and other important parameters for each band. 

1 2 200 MEMORIES • Memory capacity of 200 channels, each of 
which store frequency, mode, AGC and bandwidth. 

13 COMPUTER INTERFACE • Built-in RS-232C interface for 
advanced computer applications. 

I 4 ERGONOMIC LAYOUT ■ Front panel features easy to read color 
LCD display and thoughtful placement of controls for ease of oper- 
ation. 

15 HEAVY-DUTY POWER SUPPLY * Built-in switching power 
supply with "silent" cooling system designed for continuous 
transmission at rnaximim output 



JRC| dopon Radio Co., JM. 



430 Park Ave.. 2nd Floor New York ; NY 10022 Phone: {212) 355-1180 Fax: (212) 319-5227 

CIRCLE 159 ON READER SERVICE CARD 




Connect to h 





♦ ♦ 



A full range of ceilula 
antennas is available: hole 
mount, magnetic mount, 
on-glass and base station. 





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fOO 1/4 





MICROCELL MAG 





SGM 900 



46049 VOLTA MANTOVANA • MN - ITALY ■ Tel. (39) 376/80 1 5 1 5 - Fax (39) 376/801 254 

NORTH AMERICA OFFICE: TORONTO - CANADA - TEL {5 19} 650 9277 - Fox (519) 650 1779